How the calculations workEvery number on this site is computed on your own device from published astronomical series and the traditional rules. This page says exactly which series and which rules, and which reading was chosen where the texts disagree.

Mercury, Venus, Mars, Jupiter, Saturn and the Earth follow the VSOP87D planetary theory of Bretagnon and Francou, read from the IMCCE coefficient files themselves. The full theory has 25,659 terms; 2,359 are kept, chosen per body so that the truncation costs under an arc-second between 1750 and 2250. The heliocentric position becomes geocentric by subtracting the Earth, light-time is corrected, aberration and nutation are added, and the Sun is the Earth's position reversed. Against the JPL Horizons ephemeris the worst residual over 1850 to 2199 is 0.7 arc-seconds in longitude, and the remaining error is the abbreviated nutation shared by every body. Outside the years 1000 to 3000 the older JPL Keplerian elements take over, and every chart carries a flag once it leaves the window the series is sized for.

The Moon follows the ELP2000-82B lunar theory of Chapront-Touzé and Chapront, again from the IMCCE series files, truncated to about an arc-second, and referred to the ecliptic of date with nutation. Where that module cannot load, the Meeus chapter 47 series stands in, at about ten arc-seconds.

Rahu and Ketu are the mean ascending and descending nodes of the Moon's orbit by default, from the Meeus 47.7 series, with Ketu exactly opposite Rahu. The true node is available as an option: it comes from the osculating orbit, the node of the plane defined by the Moon's instantaneous position and velocity, and swings up to about 1.7 degrees either side of the mean node. Both are shown as retrograde, which is their natural motion.

Solar eclipses carry their Besselian elements: the shadow axis is projected onto the fundamental plane from the apparent Sun and Moon, the elements are fitted over six hours, and an observer's contacts, magnitude, obscuration and duration follow by iteration on the fundamental-plane distance. The contacts land within about a minute of the published circumstances for the eclipses of 2017, 2019, 2023 and 2024.

Civil time is converted to Universal Time with the time zone you enter, then to Terrestrial Time with Delta T from the Espenak and Meeus polynomials. From 2005 onwards those polynomials overshoot the measurements, so a fit through the observed values is used instead, 64.69 seconds in 2005 and 67.64 seconds in 2015 with a shallow rise after that.

From tropical to sidereal

Indian astrology works in the sidereal zodiac, so the ayanamsa is subtracted from every tropical longitude. Lahiri is the default. It is the Chitrapaksha ayanamsa of the Indian calendar: 22.460148 degrees at the start of 1900, plus the general precession in longitude. Raman runs a constant 1 degree 27 arc-minutes 31 arc-seconds behind Lahiri. Krishnamurti, the KP ayanamsa, runs a constant 6 arc-minutes 10 arc-seconds behind it. Lahiri and KP agree with the Swiss Ephemeris values to within about 15 arc-seconds over 1900 to 2100; Raman runs about 46 arc-seconds below the Swiss figure. Both are far finer than anything derived from them here. Six more ayanamsas can be chosen; they are set out in the next section.

Lagna, houses and navamsa

The lagna is the ecliptic longitude rising on the eastern horizon, computed from the local sidereal time, the true obliquity and the latitude of the birth place, then made sidereal. By default houses are whole sign, the South Indian practice: the lagna's whole rasi is the first house, the next rasi the second, and so on, so a graha's house follows from its rasi alone. Four other house systems can be chosen on the Settings page; the next section sets them out.

A nakshatra spans 13 degrees 20 arc-minutes and a pada a quarter of that, 3 degrees 20 arc-minutes. The navamsa sign is the same 3 degrees 20 arc-minutes division counted on from Mesham for Mesham, which is the standard rule and puts the navamsa of the first point of every movable sign back at the sign itself.

Shown on Settings.

Four choices on the Settings page change the arithmetic on every page. They are kept on this device. Left alone, they are the almanac's own: the Lahiri ayanamsa, whole-sign houses, the mean lunar node, and sunrise at the Sun's upper edge with refraction.

Nine ayanamsas

Lahiri, Raman and KP

The three the app has always carried, described in the section above. Each is a polynomial pinned to Lahiri.

True Chitrapaksha and Pushya-paksha

These follow a star. The ayanamsa is worked out afresh at every instant, so that the star sits exactly at its nominal sidereal degree. True Chitrapaksha holds Spica, the star of Chitra, at 180°. Pushya-paksha holds δ Cancri, the star of Pushya, at 106°, which is 16° of Kadagam. Each star's place and proper motion are the Hipparcos values (van Leeuwen, 2007). Precession follows Meeus chapter 21. Nutation and annual aberration are then added, so the star is in the same frame as the planets.

Fagan–Bradley, Sri Yukteshwar and Sassanian

These are fixed at one instant and carried forward by the general precession in longitude (Lieske, 1977). The epochs and values are the Swiss Ephemeris definitions. Fagan–Bradley is 24.042044° at 1950.0, the standard of Western sidereal astrology. Sri Yukteshwar is 360° less 338.917778° at 1900, as David Cochrane reduced The Holy Science. Sassanian is zero in 564 CE, the epoch of the Persian Zij-i Shah.

Custom

Your own value on 1 January 2000, carried forward by the same precession. It can be anything from 0° to 40°. It starts at 23.8565°, Lahiri's own value, so choosing it changes nothing until a number is typed.

Five house systems

This choice moves only the house a graha is counted in. The signs, the stars and the drawn rasi chart stay as they are. Wherever a page reads a graha's house from its chart, it takes it from the system chosen.

Whole sign

The default. Each sign is one house, counted from the lagna's sign. This is the rasi chart of every Tamil almanac, and what the dosha and porutham rules count by.

Sripati

The lagna and the meridian cut the sky into four quadrants, and each quadrant is divided into three equal parts of ecliptic longitude. The twelve points are the middles of the bhavas. Each bhava runs from the midpoint before its middle to the midpoint after it.

Equal

Twelve houses of exactly 30°, the first beginning at the lagna degree.

Porphyry

The same divided quadrants as Sripati, but each point is taken as the start of its house, as Western Porphyry charts do.

Placidus

Each quadrant is divided by the time its degrees take to rise and to culminate. The cusps are found by the semi-arc method, iterated until they settle. This is the system KP reads.

Near and beyond the polar circles the quadrant systems stop being well behaved. The cusps are still worked out there, but the engine flags them, and they should not be read.

Rahu and Ketu

The mean node is the default and the true node is the option. Both are described under Ephemeris and accuracy above.

Which sunrise

Almanacs do not agree on what sunrise means, and the difference is minutes. The default is the first gleam of the Sun's upper edge over a level horizon. At that moment the Sun's centre is 50′ below the true horizon: 16′ for its half-width and 34′ for the bending of light by the air. That is the convention of Meeus, the Nautical Almanac and the Indian Astronomical Ephemeris, and the sunrise the Rashtriya Panchang prints.

The Surya Siddhanta instead takes the Sun's centre on the true horizon, with no air. Some Tamil almanacs still print that sunrise. At Chennai it comes 3.4 to 3.8 minutes after the default one, and sunset comes as much before. The two mixed choices, the upper edge without refraction and the centre with it, are offered for completeness. The Sun's half-width is taken as its mean 16′; the true value moves sunrise by under ten seconds in India.

Everything that counts from sunrise follows this choice: the panchangam and the calendars, the muhurtham windows, Rahu kaal and the other day windows, and the chart values that start from sunrise.

The Ephemeris table

The Ephemeris page prints the nine grahas over a range of dates, as the back of an almanac does. Every row is a full chart cast for that instant, so its numbers are the ones the horoscope pages use. Rows can be a day, an hour or a week apart, up to 400 of them. An hourly table adds the ascendant for the place. Times are local clock times at one fixed offset from UTC. A range that crosses a daylight-saving change keeps the offset of its first day; India has none, so there it never matters. Minutes are cut, not rounded, so 29°59.9′ stays in its sign. The table can be copied as text or saved as CSV.

Each porutham is graded uttamam, a full match, madhyamam, a partial match, or adhamam, no match. A full match scores 1, a partial match ½ and no match 0, so the total runs from 0 to 10. Most of the ten rest on a single count: walk forward from the bride's star to the groom's star, counting both ends, which gives a number from 1 to 27.

Dina

Count forward from the bride’s star to the groom’s star, counting both ends. Dina porutham is present when that count is one the Tamil almanacs list: 2, 4, 6, 8, 9, 11, 13, 15, 18, 20, 24 or 26. The count also names the tara, 1 Janma, 2 Sampat, 3 Vipat, 4 Kshema, 5 Pratyak, 6 Sadhaka, 7 Naidhana, 8 Mitra, 9 Parama Mitra, and the older reading takes every tara but the 1st, 3rd, 5th and 7th instead; it is kept as an option. When both have the same star the almanac’s own list decides: Rohini, Thiruvathirai, Magam, Hastham, Visakam, Thiruvonam, Uthirattathi and Revathi may be shared, eight others never, and the rest are a second choice.

Gana

Every star belongs to the Deva, Manushya or Rakshasa gana, the temperament groups. The same gana on both sides is a full match, and so is a Deva groom with a Manushya bride; a Manushya groom with a Deva bride is a partial match. Any pairing in which one side is Rakshasa and the other is not is treated as a clash and does not match.

Mahendra

The same count from the bride’s star to the groom’s star. Mahendra is present only when the count is 4, 7, 10, 13, 16, 19, 22 or 25, that is every third star from the fourth. Any other count does not match. This porutham is read for children and the growth of the family.

Stree Deergha

The groom’s star should lie well ahead of the bride’s. A count above 13 is a full match, a count of 8 to 13 is partial, and 7 or less does not match.

Yoni

Each star carries an animal and a sex, fourteen animals in all. In the Tamil reading only the seven pairs of born enemies fail: cow and tiger, elephant and lion, horse and buffalo, dog and deer, rat and cat, sheep and monkey, serpent and mongoose. Every other pairing matches. The fourteen by fourteen koota table, which scores each pair 0 to 4 and is what the Ashta Koota uses, can be asked for instead.

Rasi

Count from the bride’s rasi to the groom’s rasi, counting both ends. One rasi agrees; the 7th, samasaptama, is the best placement, except Kadagam with Magaram and Simmam with Kumbam, the two pairs the almanacs exclude; the 9th, 10th and 11th are matches; the 3rd and 5th are middling; the 2nd, 4th, 8th and 12th do not match. The 6th is shashtashtaka and does not match unless the pair is one of the six favourable ones the almanacs list. The older reading, “the 7th place or beyond, or the same rasi”, is kept as an option.

Rasi Adhipathi

The two rasi lords are compared under the natural friendships. The same lord on both sides is a full match. Mutual friends, or a friend with a neutral, is a full match. Two neutrals, or a friend with an enemy, is partial. A neutral with an enemy, or two enemies, does not match.

Vasya

Each rasi is naturally drawn to one or two others, its vasya rasis. The table is read from the bride’s rasi: the groom’s rasi in her list is a full match, hers in his list alone is a partial one, and neither does not match. A second published list, where either direction counts, is kept as an option.

Rajju

The twenty seven stars are divided into five body groups: Siro the head, Kanta the neck, Nabhi the navel, Uru the thigh and Pada the foot. The two stars must fall in different groups. The same rajju on both sides is the strongest objection in Tamil matching and each group carries its own traditional warning, so this is one of the two checks that can end the reading on its own.

Vedha

Fifteen pairs of stars are held to obstruct each other: twelve ordinary pairs, and Mirugasirisham, Chithirai and Avittam, the three Siro-rajju stars, which are vedha to one another. If the two stars are exactly such a pair the porutham fails and is treated as a rejection.

How the total is read

If Rajju or Vedha fails the verdict is "not recommended" whatever the other nine did, because that is how the tradition treats them. Otherwise a score of 8 or more is an excellent match, 6 or more a good match, 5 is borderline and worth a conversation with the family astrologer, and below 5 is a poor match.

Ashta Koota scores eight kootas out of 36 points in all. It is not the Tamil method and it is shown here because many families are asked for it. Where the two methods disagree, the ten poruthams are the ones a Tamil astrologer will use.

The Nadi rule deserves its own sentence. Every star belongs to one of three nadis, aadi, madhya or antya, which are linked to the vata, pitta and kapha constitutions. Different nadis score the full 8 points. The same nadi on both sides scores 0 and is called Nadi dosha, which North Indian astrologers usually treat as a rejection on its own, since it is read as a matter of health and children.

A total of 33 to 36 is excellent, 25 to 32 good, 18 to 24 average, and below 18 is not recommended.

Sevvai dosham

Sevvai, that is Mars, is read from three reference points: the lagna, the Moon and Venus. Counting from each of them, the 1st, 2nd, 4th, 7th, 8th and 12th houses are the dosha houses. The 2nd is included because that is the South Indian convention; lists that leave it out will find the dosham less often. If Sevvai falls in a dosha house from any of the three, the dosham is present.

Several classical placements cancel it. Sevvai exalted in Magaram or in its own Mesham or Viruchigam. Sevvai conjunct Guru, or in one of Guru's signs Dhanusu and Meenam. Sevvai conjunct Sani or Rahu. And five house-specific exemptions counted from the lagna: the 2nd house in Mithunam or Kanni, the 4th in Mesham or Viruchigam, the 7th in Kadagam or Magaram, the 8th in Dhanusu or Meenam, and the 12th in Rishabam or Thulam. With no cancellation the dosham is called strong, with at least one it is called mild.

For a match, neither side having it is clear and both sides having it is traditionally read as matched and acceptable. When only one side has it, a mild dosham is usually accepted and a strong one is where most astrologers will want a remedy or will advise against the match.

Papa samya

Papa samya weighs the malefics instead of just noting them. Sevvai and Sani count 1 point each, the Sun, Rahu and Ketu ½ point each, counted whenever they sit in one of the same dosha houses from the lagna, from the Moon and from Venus. A planet that is exalted or in its own sign counts half of its usual value. The totals are then compared: the bride's total should not exceed the groom's, with a half point allowed on top before the pairing is called unbalanced.

Dasa sandhi

A sandhi is the join between two mahadashas. The check looks at today's date and asks, for each chart, how far it is from the nearest mahadasha change. When both charts change within a year of each other the pairing is flagged as dasa sandhi dosha, on the reasoning that a marriage should not begin while both lives are turning over at once. One side alone near a change is not a dosha.

Kala sarpa

Kala sarpa dosham is present when all seven grahas from the Sun to Sani lie on one side of the Rahu and Ketu axis, with nothing on the other side. The page reports it because families ask, and names the grahas that break the arc when it is absent. It is not a matching criterion here, only a note for the astrologer.

Vimshottari divides a notional 120-year life among the nine grahas in a fixed order and with fixed lengths: Ketu 7 years, Sukran 20, Suriyan 6, Chandran 10, Sevvai 7, Rahu 18, Guru 16, Sani 19 and Budhan 17. The order starts from Aswini, so the 1st, 10th and 19th nakshatras belong to Ketu, the 2nd, 11th and 20th to Sukran, and so on through the twenty seven.

The birth Moon's nakshatra names the lord of the mahadasha running at birth, and how far the Moon has already travelled through that nakshatra says how much of the period is already spent. The remainder is the balance of dasha at birth. From there the periods run end to end in the fixed order until the 120 years are used up. Each mahadasha is subdivided into nine antardashas in the same order, each one in proportion to its own lord's share of the 120 years, so Sukran's antardasha inside Sani's mahadasha lasts 19 times 20 divided by 120 years. A dasha year is taken as 365.25 days.

Five levels

Below the antardasha, the bhukti, come three more levels. In Tamil they are the antaram, the sookshmam and the pranam; in Sanskrit the pratyantara, the sookshma and the prana dasha. Each level divides its parent in the same 7 : 20 : 6 : 10 : 7 : 18 : 16 : 19 : 17 proportion, starting with the parent's own lord. A prana dasha lasts hours rather than days, so its dates carry a clock time.

The whole tree holds 9 × 9 × 9 × 9 × 9, that is 59,049, prana periods. So a level is worked out only when it is opened, and then kept. The first mahadasha began before birth. Its sub-periods are laid out from that notional start and then cut at birth, which is how the antardashas have always been built.

Dasha sandhi

A sandhi is the joint between two periods. The outgoing lord still has a say, and the incoming one is not yet settled. Here a date is in sandhi when it falls in the first or the last 5% of a period. The test is made at every level, from the mahadasha down. For the first mahadasha the 5% is measured from its notional start before birth, not from the birth.

This is a different rule from the dasa sandhi dosha of matching, under Chart-based checks above. That one asks whether two charts change mahadasha within a year of each other.

What changes on a date

The Dasha page lists every change of period between two dates, down to the level chosen. When a mahadasha changes, the change is listed once, as a mahadasha change. The bhukti and the levels below change with it, which is what a family means by "the dasha changes".

Shown on Dasha and Year ahead.

The Dasha page offers eight systems. Vimshottari is above; the other seven are here. Chara, Narayana, Sthira and Mandook start from the lagna, so they need the time of birth. The rest start from the Moon.

Ashtottari, 108 years

Eight lords: the Sun 6 years, the Moon 15, Mars 8, Mercury 17, Saturn 10, Jupiter 19, Rahu 12 and Venus 21. The stars are handed out in runs of 3, 4, 3, 4, 3, 4, 3 and 3, starting at Thiruvathirai with the Sun. The balance at birth is the part of the lord's whole run of stars still to be crossed. The classical rule reads Ashtottari only when Rahu is in a kendra or trikona from the sign of the lagna lord. That test is reported with the table and never enforced. The antardashas and pratyantaras follow the same proportions, as BPHS gives them.

Yogini, 36 years

Eight yoginis: Mangala 1 year (the Moon), Pingala 2 (the Sun), Dhanya 3 (Jupiter), Bhramari 4 (Mars), Bhadrika 5 (Mercury), Ulka 6 (Saturn), Siddha 7 (Venus) and Sankata 8 (Rahu). The yogini running at birth is the birth star's number plus 3, divided by 8; a remainder of 0 is Sankata. The balance is the part of the star the Moon has still to cross. The cycle is short, so the page runs it four times to cover a life. Sub-periods divide in proportion, three levels deep.

Chara

Jaimini's sign dasha, in the form K. N. Rao teaches. The lagna's sign decides the direction: forward from an odd-footed sign (Mesham, Rishabam, Mithunam, Thulam, Viruchigam, Dhanusu), backward from the others. A sign's years are the count from it to the sign its lord occupies, less one, counted the same way round. A lord in its own sign gives 12. Viruchigam is ruled by Ketu when Ketu sits in it, and Kumbam by Rahu when Rahu sits in it. The antardashas are twelve equal parts, opening with the sign itself. Other schools count the years differently; this one form is used.

Kalachakra

A sign dasha opened by the Moon's pada. Parashara calls it the most respected of the dashas (BPHS, the Kalachakra chapter). The table is the standard one, as P. V. R. Narasimha Rao sets it out in Vedic Astrology: An Integrated Approach. The 27 stars fall in nine groups of three: five groups are savya, read clockwise, and four apasavya, read the other way. Each pada has its own row of nine signs.

Every sign has fixed years: Mesham 7, Rishabam 16, Mithunam 9, Kadagam 21, Simmam 5, Kanni 9, Thulam 16, Viruchigam 7, Dhanusu 10, Magaram 4, Kumbam 4 and Meenam 10. A row's nine signs add up to its paramayus, the span of life the pada promises: 100, 85, 83 or 86 years. The part of the pada the Moon had crossed at birth, times the paramayus, is the time already spent. After the ninth sign the dasha carries on with the next pada's row; some readers repeat the birth row instead. The rows produce the famous jumps across the wheel: the lion's backward glance, the frog's leap and the monkey's step back. The antardashas run the same nine signs from the mahadasha's own sign, in proportion. The texts stop at two levels, and so does the page.

Narayana

The Jaimini dasha most read today for the outer life: career, moves, marriage. The form is Sanjay Rath's and P. V. R. Narasimha Rao's. It opens from the stronger of the lagna and the 7th. It runs forward from an odd sign and backward from an even one. Sani in the opening sign makes it run forward whatever the sign; Ketu there reverses the direction. From a movable sign the signs follow one another. From a fixed sign every sixth sign is taken. From a dual sign the kendras come first, then the panaparas, then the apoklimas.

The years are counted as in Chara. One year is added when the lord is exalted and one taken off when it is debilitated. When a sign has two lords, Viruchigam (Sevvai and Ketu) or Kumbam (Sani and Rahu), the lord not sitting in the sign is used. With both there the sign gets 12. With neither there, the lord with more grahas beside it is used, and then the one further into its sign. A second cycle follows, each sign taking 12 less its first-cycle years, so every sign has twelve years over the two.

Sthira, 96 years

The "fixed" dasha, read for longevity. It opens from the sign of the Brahma graha. Brahma is found from the stronger of the lagna and the 7th: among the lords of the 6th, 8th and 12th from it, the strongest one standing in an odd sign in the 7th to 12th house from it. Sani is never Brahma. When no lord qualifies, the strongest of them in any odd sign is taken, and failing that the strongest of the three. The signs then follow one another, forward from an odd sign and backward from an even one. Each has fixed years: 7 for a movable sign, 8 for a fixed sign and 9 for a dual sign.

Mandook, 96 years

The "frog" dasha. It opens from the stronger of the lagna and the 7th and leaps three signs at a time: the kendras, then the panaparas, then the apoklimas. It runs forward from an odd sign and backward from an even one. The years are as in Sthira.

Which sign is stronger

Narayana, Sthira and Mandook all need the stronger of two signs. Six Jaimini tests are applied in order, stopping at the first that separates them. The sign with more grahas. The sign joined or seen, by rasi drishti, by more of Guru, Budhan and its own lord. The sign with more exalted grahas. A dual sign over a fixed one, and a fixed sign over a movable one. The sign whose lord stands in a sign of the other oddity. The sign whose lord has gone further into its own sign. When nothing separates them, the lagna is taken. The reason is given beside the table.

For Narayana, Sthira and Mandook only the sign periods themselves are built. The schools divide them further in ways that differ too much for one to be imposed.

All five are computed for the moment of sunrise at the place you choose, and each one is followed forward to the minute it ends. The end time is found by stepping ahead in five-minute intervals until the value changes, then bisecting that interval down to about a tenth of a second.

Tithi

The Moon's longitude minus the Sun's, in steps of 12 degrees, so 30 tithis fill a lunar month. Tithis 1 to 15 are the bright fortnight, Shukla paksha, and 16 to 30 the dark fortnight, Krishna paksha. The fifteenth of each is Pournami and Amavasai respectively.

Vara

The weekday, Sunday through Saturday, taken from the local civil date.

Nakshatra

The sidereal Moon in steps of 13 degrees 20 arc-minutes, twenty seven in all, with the pada as the quarter within it.

Yoga

The sum of the sidereal Moon and Sun longitudes, again in steps of 13 degrees 20 arc-minutes, giving the twenty seven yogas from Vishkambha to Vaidhriti.

Karana

Half a tithi, 6 degrees of Moon minus Sun, so 60 fill a lunar month. The first is Kimstughna, numbers 2 to 57 cycle through the seven movable karanas beginning with Bava, and the last three are Shakuni, Chatushpada and Naga.

Rahu kaal, Yamaganda, Gulika and Abhijit

The daylight from sunrise to sunset is cut into eight equal parts, and each weekday assigns one part to each window. Rahu kaal takes the 8th part on Sunday, the 2nd on Monday, the 7th on Tuesday, the 5th on Wednesday, the 6th on Thursday, the 4th on Friday and the 3rd on Saturday. Yamaganda takes the 5th, 4th, 3rd, 2nd, 1st, 7th and 6th part over the same seven days. Gulika takes the 7th, 6th, 5th, 4th, 3rd, 2nd and 1st, one earlier each day from Sunday to Saturday. Because the parts are an eighth of the actual daylight, these windows are longer in summer and shorter in winter and move with the place, which is why they differ from a printed almanac made for another town.

Abhijit is the auspicious muhurtam around noon. The daylight is divided into fifteen equal muhurtas and Abhijit is the eighth of them, the one that straddles the Sun's transit.

Where the Sun neither rises nor sets, far enough north or south, the windows have no meaning. A nominal twelve-hour day centred on the transit is used instead so that the rest of the panchangam can still be shown.

Gowri panchangam

The daylight is cut into eight equal parts and the night likewise. Each part carries one of eight names in a fixed cycle, Uthi, Amirdha, Rogam, Laabam, Dhanam, Sugam, Soram, Visham. The day sequence starts one name later each weekday, Sunday from Uthi, Monday from Amirdha, and so on. The night sequence starts three names earlier than the same weekday's day sequence. Amirdha, Dhanam, Laabam, Sugam and Uthi are good; Rogam, Soram and Visham are to be avoided.

Nalla neram

Almanacs print two good windows a day and differ in how they pick them. Here they are the good Gowri parts of the day that do not touch Rahu kaal, Yamaganda or Gulika: the earliest such part in the morning half and the earliest in the afternoon half, each capped at ninety minutes.

Varjyam

Each nakshatra has a fixed point inside its own span, counted in ghatis of that nakshatra's sixty-ghati length, from which four ghatis are to be avoided. The table runs Aswini 50, Bharani 24, Karthigai 30, Rohini 40, Mirugasirisham 14, Thiruvathirai 21, Punarpoosam 30, Poosam 20, Ayilyam 32, Magam 30, Pooram 20, Uthiram 18, Hastham 21, Chithirai 20, Swathi 14, Visakam 14, Anusham 10, Kettai 14, Moolam 56, Pooradam 24, Uthiradam 20, Thiruvonam 10, Avittam 10, Sadayam 18, Poorattathi 16, Uthirattathi 24, Revathi 30. Because a ghati here is one sixtieth of the nakshatra's actual duration, it runs about 21 to 27 minutes rather than a fixed 24.

Amrita kalam

Begins twenty ghatis after the start of the same nakshatra's Varjyam and also lasts four ghatis. For Moolam that lands past the nakshatra's own end, which is why an Amrita kalam from a star that has already ended can appear on the day.

Durmuhurtham

The daylight is divided into fifteen muhurtas and the night into fifteen. The inauspicious ones are fixed by weekday: Sunday the 14th of the day; Monday the 9th and 12th; Tuesday the 4th of the day and the 7th of the night; Wednesday the 8th; Thursday the 6th and 12th; Friday the 4th and 9th; Saturday the 1st and 2nd.

Horai

Twenty four planetary hours from sunrise, twelve of the day's length and twelve of the night's. The first belongs to the weekday's lord, then the hours follow the order Sun, Venus, Mercury, Moon, Saturn, Jupiter, Mars and repeat, so the 25th hour lands on the next day's lord. Hours of the Moon, Mercury, Jupiter and Venus are read as good, the Sun's as neutral, Mars's and Saturn's as unfavourable.

Shown on Panchangam and Daily rasi.

A day can be good in general and still wrong for one person. The two checks every South Indian almanac makes for that come from Muhurta Chintamani, and both start from the birth Moon.

Tarabala

Count from the birth star to the day's star, the birth star being the 1st, and reduce the count to 1 to 9. The nine taras are Janma, Sampat, Vipat, Kshema, Pratyak, Sadhana, Naidhana, Mitra and Parama Mitra. Sampat, Kshema, Sadhana, Mitra and Parama Mitra are good. Vipat, Pratyak and Naidhana are bad. Janma, the birth star itself, is mixed: it is kept for worship, but avoided for travel, medicine and new ventures. The day's star is the one at sunrise.

Chandrabala

Count from the birth Moon's sign to the day's Moon sign, the birth sign being the 1st. The 1st, 3rd, 6th, 7th, 10th and 11th are good. The 2nd, 5th and 9th are mixed. The 4th, 8th and 12th are bad; the 8th is Chandrashtama.

Both together

A day is good for the person with a good tara and a good Chandrabala. It is best avoided on Chandrashtama, with a bad tara, or with the Moon in the 4th or 12th. Anything else is fair. Muhurta Chintamani gives the Moon more weight in the bright fortnight and the stars in the dark one (śukle candrabalaṃ, kṛṣṇe tārābalam). The fortnight is reported, but both checks decide.

Pancha pakshi

The Tamil five-bird system (பஞ்ச பட்சி சாஸ்திரம்). A person's bird comes from the birth star and the fortnight of birth. In the bright fortnight, Aswini to Mirugasirisham is the Vulture, Thiruvathirai to Pooram the Owl, Uthiram to Visakam the Crow, Anusham to Uthiradam the Cock, and Thiruvonam to Revathi the Peacock. In the dark fortnight the same groups take the birds in reverse order.

Sunrise to sunset is cut into five equal yamas, and sunset to the next sunrise into five more. In every yama each bird is ruling, eating, walking, sleeping or dying, strongest first. Ruling and eating are the times to act. Walking is middling. Sleeping and dying are avoided. Each yama divides into five parts in Prof. Pulippani's proportions: in a yama of 144 minutes, eating 30, walking 36, ruling 48, sleeping 18 and dying 12, scaled to the real yama. The fortnight at sunrise governs the whole day and night.

The activity table is the one the PyJHora project ships. It agrees with every dark-fortnight yama printed in Pulippani's Panchapakshi Sastra, and the tests check each one. It also keeps the tradition's structure: each bird runs through its fortnight's order of the five activities, and no two birds share an activity in a yama. The "mirror" tables of another program break that structure and were not used.

Shown on Panchangam and Guides.

These are table lookups, with no astronomy beyond the day's star and tithi. The classical tables are those of Muhurta Chintamani (Ramacharya, 1600), in the form Ernst Wilhelm tabulated them, which is what drikpanchang and most North and South Indian panchangams print. A tithi is counted inside its fortnight, 1 to 15, because the tables name tithis that way.

The good ones

Amrita Siddhi and Sarvartha Siddhi pair a weekday with a star. The same text excepts three pairs for marriage, travel and entering a new house: Aswini on a Tuesday, Poosam on a Thursday and Rohini on a Saturday. They stay good for everything else. Siddha pairs a weekday with a class of tithi. Guru Pushya and Ravi Pushya are Poosam on a Thursday and on a Sunday. Ravi yoga is the Moon's star 4, 6, 9, 10, 13 or 20 stars on from the Sun's, the Sun's own being the 1st, as drikpanchang prints it.

Dwipushkara and Tripushkara

A Sunday, Tuesday or Saturday, with the 2nd, 7th or 12th tithi, and a star split across two signs. A star with three padas in one sign and one in the next (Karthigai, Punarpoosam, Uthiram, Visakam, Uthiradam, Poorattathi) gives Tripushkara. A star split two and two (Mirugasirisham, Chithirai, Avittam) gives Dwipushkara. Whatever is begun is said to repeat three times or twice: good for a gain, bad for a loss or anything meant to happen once.

The bad ones

Dagdha, Visha and Hutasana pair a weekday with a tithi, and Mrityu a weekday with a star. For Dagdha on a Wednesday the text also allows the 2nd tithi; the table's 3rd is used, as panchangams print it.

The Tamil naal yogam

Every Tamil daily calendar prints one of four yogams for the day from its weekday and star: Siddha, Amirtha, Marana or Prabalarishta. The table is the one Tamil calendars print, as given by Ungal Vazhkkai Vazhikatti. The tests check that every classical Mrityu pair falls on Marana, and every Amrita Siddhi pair on Siddha or Amirtha. A shorter table on another Tamil site misses the Mrityu pairs, so it was not used.

Panchaka, the count

The South Indian check for a muhurtam. Add the tithi (1 to 30, from Shukla Prathamai), the weekday (Sunday 1), the star (Aswini 1) and the rising sign (Mesham 1), and divide by 9. A remainder of 1 is Mrityu, 2 Agni, 4 Raja, 6 Chora and 8 Roga panchaka; 0, 3, 5 and 7 are clear. The rule is Muhurta Chintamani's. Which work each one spoils follows B. V. Raman's Muhurtha: Raja for work and dealings with the government, Raja and Agni for building a house, Chora for travel, Roga and Mrityu for marriage and upanayanam. The rising sign changes about every two hours, so a whole day is neither clear nor blemished; the twelve lagnas are listed instead.

Panchak, the North Indian stars

The Moon from 0° of Kumbam, the middle of Avittam, to the end of Revathi. Muhurta Chintamani forbids five kinds of work in it: gathering wood, grass or fuel, covering a roof, travelling south, making a bed, and cremation, which may still go ahead with the remedy of five kusha-grass figures. A Panchak is named for the weekday it begins on.

Shoolam, the direction not to travel

The weekday's disha shoolam is the table of every panchangam: Monday and Saturday east, Thursday south, Sunday and Friday west, Tuesday and Wednesday north. If the journey cannot wait, the Tamil remedy goes with the direction: a little curd for east, jaggery for west, milk for north, sesame oil for south. The North Indian remedy goes with the weekday instead. The star shoolam uses Muhurta Chintamani's four stars: Kettai closes the east, Poorattathi the south, Rohini the west and Uthiram the north.

Three more are read against the direction of travel: Yogini by the tithi, the Moon by its sign, and Rahu by the weekday. Yogini straight ahead, the Moon behind, or Rahu straight ahead closes a direction. Yogini on the right or the Moon on the left is a caution, a loss of money. The shoolams are for journeys, a move or a new undertaking, not the daily commute. The travel flow on the Guides page uses all of this.

Each day in the range you give starts at zero and every factor adds or subtracts. Three factors are fatal: whatever the total, they force the day to "avoid".

• Tamil month. Aadi, Purattasi and Margazhi are not used for weddings, and that is fatal. The other nine months add 2.
• Weekday. Monday, Wednesday, Thursday and Friday add 2. Sunday is acceptable and adds nothing. A Tuesday or a Saturday rules the day out, as no Tamil almanac prints a wedding muhurtham on either.
• Tithi at sunrise. The seven wedding tithis, Dwitiyai, Thritiyai, Panchami, Saptami, Dasami, Ekadasi and Trayodasi, add 2, counted in the bright fortnight and in the dark one as far as Dasami. Pournami and the dark fortnight’s Ekadasi and Trayodasi score nothing. Every other tithi, including Prathamai, Chaturthi, Shashti, Ashtami, Navami, Dwadasi, Chaturdasi and Amavasai, subtracts 6.
• Nakshatra at sunrise. The marriage stars Rohini, Mrigashira, Magha, Uttara Phalguni, Hasta, Swati, Anuradha, Mula, Uttara Ashadha, Shravana, Uttara Bhadrapada and Revati add 3. Ten stars are avoided and subtract 6: Bharani, Krittika, Ardra, Ashlesha, Purva Phalguni, Vishakha, Jyeshtha, Purva Ashadha, Shatabhisha and Purva Bhadrapada. The remaining five are neutral.
• Vishti karana. Vishti, also called Bhadra, running at sunrise subtracts 4.
• The couple. Chandrashtama, meaning the day's Moon sign is the 8th from that person's rasi, is fatal and is checked for each of them. The day's nakshatra being someone's janma nakshatra subtracts 4. The Moon in the 1st or the 12th from a rasi is only a mild caution and subtracts 1.
• Lagna windows. Mithunam, Kanni and Thulam are the best wedding lagnas, the three every source names, and Rishabam, Kadagam, Dhanusu, Kumbam and Meenam are acceptable. Mesham, Simmam, Viruchigam and Magaram are not used. Each usable window adds 1, at most 2 in all.

A window is found by walking the sidereal lagna through the daylight hours in five-minute steps and bisecting each sign change, then cutting out Rahu kaal, Yamaganda and Gulika kaal. What is left counts only if at least 45 minutes remain in one piece, and the page marks any window that overlaps Abhijit.

A day scoring 7 or more is excellent, 4 or more good, 1 or more fair, and anything below that is best avoided. A search covers at most 120 days at a time.

The Tamil month is the sidereal sign the Sun stands in. Chithirai is the Sun in Mesham, Vaikasi in Rishabam, and so on to Panguni in Meenam. A month begins on the day of the sankramana, the Sun's ingress into the sign, when that ingress happens before local sunset. When it happens after sunset the month begins the next day, which is why a Tamil date can differ by one day between two towns.

Which Sun: vakya and thirukanitha

Two Tamil almanacs can print different dates for the same day, and both are right by their own rule. The thirukanitha reckoning takes the Sun as modern astronomy computes it. The vakya reckoning takes the Sun of the classical Vakyakarana tradition, whose year length and epicycle come down from Aryabhata, and which the Pambu panchangam and most printed Tamil wall calendars still follow. The vakya Sun runs a few hours behind the true one, which is enough to move the first of a month by a day about a third of the time.

This site reckons the Tamil month by vakya, because that is what most readers have on the wall beside them. Every other calendar here keeps the true Sun: Malayalam, Telugu, Kannada and the north Indian months are all thirukanitha, as their own almanacs are. The reckoning is named beside the Tamil date on the home card and the panchangam, and either one can be chosen under Settings.

One honest limit. The vakya Sun as printed is not a single formula but a family of them: different almanac houses round to different places and correct by hand, so the published month starts scatter by two or three hours around any one computation of them. Ours agrees with 114 of 132 published month starts between 2016 and 2026, and 34 of 36 for 2025 to 2027. Where your almanac differs, its own reckoning is the one to keep.

Years run through the 60-year Jovian cycle. Prabhava began on 14 April 1987, so the year that began in April 2024 is Krodhi, 2025 Visuvavasu and 2026 Parabhava. Thai, Maasi and Panguni belong to the year that began the previous April.

Festivals fixed by a tithi are placed in the amanta lunar month that contains the matching sankranti, so Chaitra is the lunar month holding the Mesha sankranti and Bhadrapada the one holding the Kanya sankranti. That is what keeps Vinayagar Chaturthi and Deepavali in the right place in an adhika masa year, when a Tamil solar month holds two new moons.

Each festival also names the instant at which its tithi or nakshatra has to be running, because a tithi rarely covers a whole day. The instants used are sunrise, midday, aparahna in the afternoon, sunset, pradosha from sunset to about 2 hours 24 minutes after it, nishita at midnight, and arunodaya 96 minutes before sunrise. Maha Shivaratri takes the Krishna Chaturdasi running at nishita, Deepavali the Krishna Chaturdasi running at arunodaya, the time of the oil bath, and Vijayadasami the Shukla Dasami at sunrise. The rule is printed next to every entry on the calendar page, so you can see which convention produced the date and compare it with your family's almanac.

Pournami, Amavasai, Ekadasi and Pradosham are generated once per lunar cycle and paksha rather than listed by hand. They belong to the monthly observances, which every tradition on this site shares; the rules are in the next section.

The same two instants drive all four calendars on this site: the sankramana, when the sidereal Sun crosses into a new rasi, and the new moon, when the Sun and the Moon have the same longitude. What differs is how each tradition turns those instants into a date.

Kerala: the aparahna rule and the Kollam era

The twelve Malayalam months map one to one onto the Tamil months, because both are the Sun's rasi: Medam is Chithirai, Edavam Vaikasi, Mithunam Aani, Karkidakam Aadi, Chingam Aavani, Kanni Purattasi, Thulam Aippasi, Vrischikam Karthigai, Dhanu Margazhi, Makaram Thai, Kumbham Maasi and Meenam Panguni.

The day the month begins is where the two part. Tamil Nadu gives the ingress day to the new month whenever the Sun enters the sign before sunset. Kerala uses the stricter aparahna limit, three fifths of the daylight after sunrise, that is sunrise plus 0.6 times the length of the day. An ingress falling between aparahna and sunset therefore starts the Malayalam month a day later than the Tamil one. That is not a rare corner: between 2024 and 2026 it happens six times, among them the Makara sankranti of 14 January 2026, which gives Thai 1 on the 14th and Makaram 1 on the 15th.

Years are counted in the Kollam era, Kollavarsham, which begins on Chingam 1 in August. The Malayalam year is the Common Era year minus 824 from Chingam 1 onwards and minus 825 before it, so 17 August 2024 was 1 Chingam 1200.

Telugu and Kannada: amanta months, adhika masa, samvatsara and Saka

Andhra, Telangana and Karnataka share one calendar and differ only in the script the names are written in. Its month is amanta and lunar: it runs from one new moon to the next and takes the name of the rasi the Sun enters inside that span. Mesha gives Chaitra, Vrishabha Vaishakha, Mithuna Jyeshtha, Karkataka Ashadha, Simha Shravana, Kanya Bhadrapada, Tula Ashwayuja, Vrischika Kartika, Dhanus Margashira, Makara Pushya, Kumbha Magha and Meena Phalguna. The fortnight is Shukla from the new moon to the full moon and Krishna after it.

A lunar month is about 29.53 days and a solar month between 29.4 and 31.4, so now and then a lunar month contains no sankranti at all. That month is adhika, an extra month; it borrows the name of the month that follows it and hosts no festival, which stay in the nija, the true, month. In 2023 the month from 18 July to 16 August was Adhika Shravana, and every Shravana festival, Varalakshmi Vratam on 25 August, Shravana Pournami on 31 August and Janmashtami on 6 September, fell in the nija Shravana that followed.

The year begins at Ugadi, Chaitra Shukla Prathama. It carries two numbers. The samvatsara is the same 60-year cycle the Tamil calendar uses, with Prabhava first: the index for the year beginning in a Common Era year Y is Y minus 1867, modulo 60, so 2024 is Krodhi, 2025 Visuvavasu and 2026 Parabhava. The Shalivahana Saka year is Y minus 78 from Ugadi and Y minus 79 before it, so Ugadi of 2024 opened Saka 1946. The ayana follows the sidereal Sun, Uttarayana from Makara to Mithuna and Dakshinayana from Karkataka to Dhanus, and the ritu is two lunar months at a time from Vasanta at Chaitra.

Prathama can begin and end between two sunrises, touching neither. When that happens the day the tithi ran on is taken, which is why Ugadi 2026 is 19 March and not the 20th.

Kerala festivals, rule by rule

Telugu and Kannada festivals, rule by rule

Monthly observances

Besides the festivals that come once a year, every lunar month brings the same short list, and the calendar and the panchangam carry it for all four traditions. Pournami and Amavasya are the tithi at sunrise. Ekadasi is taken twice a month, Shukla and Krishna, at sunrise, the second day when it runs at two. Pradosham is the Trayodasi of each fortnight running at sunset, the pradosha hour, and is called Sani Pradosham when that day is a Saturday. Sankatahara Chaturthi is the Krishna Chaturthi running at sunset, the evening the moon is looked for. Masa Sivarathri is the Krishna Chaturdasi at nishita, read by the same rule as Maha Shivaratri. Tamil Nadu and Kerala add the Shukla Chaturthi as the monthly Vinayagar Chaturthi, the Shukla Sashti as the Murugan vratam, the Krishna Ashtami as Kala Bhairava Ashtami, and the days on which Karthigai, Thiruvonam, Poosam or Ayilyam runs at sunrise. The Telugu and Kannada list keeps the tithi observances and the Krittika day.

A monthly observance is dropped from a day that already carries an annual festival, because the day is marked either way and the named festival is the one that says what it rests on. A tithi short enough to touch no sunrise, or no sunset where the rule wants one, falls back to the day it actually ran on.

Where a rule says "at sunrise" it is the udaya tithi, the tithi running at the moment the Sun rises at the place you enter. Almanacs that fix Vijayadashami or Subrahmanya Shashti by the tithi running in the afternoon instead will put those a day earlier in some years. The rule that produced each date is printed next to it on the calendar page, so the two can be compared.

North India cuts the lunar month at the full moon rather than at the new moon. The instants are the same ones the southern calendars use, and so are the tithis; only the month name moves. A purnimanta month ends at the full moon, so its Krishna paksha comes first and its Shukla paksha last, which makes the dark fortnight of a purnimanta month the dark fortnight of the amanta month one place before it. Purnimanta Kartika Krishna is amanta Ashwina Krishna. Purnimanta Bhadrapada Krishna is amanta Shravana Krishna, which is why the same night is Bhadrapada Krishna Ashtami in Varanasi and Shravana Krishna Ashtami in Hyderabad and is Janmashtami in both.

The whole conversion is one line, and the engine applies it exactly once: a Shukla day keeps its amanta month name, a Krishna day takes the name of the next month. The tithi, the paksha, the day of the fortnight and the adhika flag are carried through untouched. The twelve months are Chaitra, Vaishakha, Jyeshtha, Ashadha, Shravana, Bhadrapada, Ashwina, Kartika, Margashirsha, Pausha, Magha and Phalguna, written in Devanagari as चैत्र, वैशाख, ज्येष्ठ, आषाढ़, श्रावण, भाद्रपद, आश्विन, कार्तिक, मार्गशीर्ष, पौष, माघ and फाल्गुन.

Vikram Samvat

The North Indian year begins at Chaitra Shukla Pratipada, the same instant as Ugadi, and is numbered in the Vikram Samvat era: the Common Era year plus 57 from that day, plus 56 before it. The year that opened on 9 April 2024 is Vikram Samvat 2081. Gujarat keeps the same era and the same number but starts its year at Kartika Shukla Pratipada, the day after Diwali, so a Gujarati Vikram year runs one behind the North Indian one from Chaitra until Diwali; both are shown on the panchangam page when they differ. The 60-year samvatsara cycle is the one the southern calendars use, unchanged, so 2081 is also Krodhi and Saka 1946.

Where a rule names an instant

Unless a rule says otherwise the day is the udaya tithi, the tithi running at sunrise at the place you enter. Where an instant is named it is one of these: purvahna, the middle of the second fifth of the daylight; madhyahna, the midpoint of sunrise and sunset; sunset; pradosha, taken as the middle of the 2 hours 24 minutes after sunset; and nishita, true midnight, the midpoint of sunset and the next sunrise. Diwali is the clearest case. The Amavasya prevailing at pradosha is the one the Lakshmi puja is done in, so in 2024, when the Amavasya ran from 15:52 on 31 October to 18:16 on 1 November, Diwali fell on the evening of the 31st although the Amavasya held the sunrise of the 1st.

The festivals, rule by rule

The named Ekadashis and the monthly days

Twenty-four Ekadashis are named across an ordinary year, two to a lunar month, and the calendar prints each under its own name rather than as a bare Ekadashi: Kamada, Varuthini, Mohini, Apara, Nirjala, Yogini, Devshayani, Kamika, Shravana Putrada, Aja, Parivartini, Indira, Papankusha, Rama, Devuthani, Utpanna, Mokshada, Saphala, Pausha Putrada, Shattila, Jaya, Vijaya, Amalaki and Papmochani, in that order from Chaitra Shukla Pratipada. An adhika month brings its own pair instead, Padmini in the bright fortnight and Parama in the dark. Beside them come the same recurring days the other traditions keep, in the North Indian wording: Purnima and Amavasya at sunrise, Pradosh vrat on each Trayodashi running at sunset and called Shani Pradosh on a Saturday, Sankashti Chaturthi on the Krishna Chaturthi running at sunset and called Angarki when that day is a Tuesday, and Masik Shivratri on the Krishna Chaturdashi at nishita.

Choghadiya

Sunrise to sunset is cut into eight equal parts and sunset to the next sunrise into eight more, so a choghadiya is about 90 minutes by day at the equinox and stretches or shrinks with the season. There are seven names for eight parts, so the last part of each row repeats the first. The day sequence enters the cycle Udveg, Char, Labh, Amrit, Kaal, Shubh, Rog three names further along for each weekday, and the night sequence enters its own cycle, Shubh, Amrit, Char, Rog, Kaal, Labh, Udveg, two names further along. Amrit, Shubh and Labh are the good parts, Char is good for a journey, and Rog, Kaal and Udveg are the ones to avoid. This is the northern counterpart of the Gowri panchangam above, which cuts the same day into eight and names the parts differently.

The named muhurtas

Six windows are printed beside the choghadiya. Two are cut from the daylight or the night and move with the season; the rest are fixed lengths of clock time either side of sunrise or sunset. The times below are for a nominal day of sunrise 06:00 and sunset 18:00, which is where the figures in the definitions come from. Abhijit, the 8th of the fifteen day muhurtas, is printed with the muhurtham windows instead, and Amrit kalam belongs to the Gowri sheet, so neither is repeated here.

The choghadiya and these muhurtas are arithmetic on sunrise and sunset alone; nothing in them depends on the tithi or the nakshatra. Change the place and every boundary moves with the Sun.

Each occasion carries its own rule set: preferred and avoided lunar or Tamil months, whether Uttarayana is preferred and Chaturmasa avoided, the weekdays, the tithis, the nakshatras and, where the occasion has lagna windows, which signs count. The day's facts come from the same panchangam at sunrise the wedding finder uses, and the same point table scores each rule that applies, so a housewarming day and a wedding day are graded on one scale.

The shared tithi set is Shukla 2, 3, 5, 7, 10, 11 and 13 and Krishna 2, 3, 5, 7 and 10; the Rikta tithis 4, 9 and 14 and Amavasai are avoided. Bharani, Karthigai, Thiruvathirai, Ayilyam and Kettai are avoided unless an occasion names them. Housewarming prefers Vaishakha, Jyeshtha, Magha and Phalguna and refuses Chaturmasa; the sacred thread prefers Uttarayana and the Shukla paksha; the first haircut refuses Chaturmasa; gold buying favours Poosam and marks Akshaya Tritiya and Dhanteras; travel only marks Tuesday and Saturday weak. Combustion of Guru and Sukran, which some families check for a housewarming, is not computed and is said so on the page.

Divisional charts

Sixteen vargas from a sidereal longitude by the Parashari divisions: hora, drekkana, chaturthamsa, saptamsa, navamsa, dasamsa, dwadasamsa, shodasamsa, vimsamsa, chaturvimsamsa, bhamsa, trimsamsa with its unequal 5, 5, 8, 7, 5 portions, khavedamsa, akshavedamsa and shashtiamsa. The part is found as the floor of degrees times the division count over thirty, never by dividing the sign into fractional widths, so a boundary such as 3°20′ never lands on the wrong side. The navamsa agrees with the main chart at every degree.

Vimshopaka bala

The dignity of a planet in each varga weighted by the Shadvarga, Saptavarga, Dasavarga and Shodasavarga schemes, each summing to twenty. Own, exaltation and moolatrikona count as own; friend, neutral and enemy step down; debilitation keeps two points.

Bhava chalit

Sripati cusps: the meridian from the local sidereal time and the obliquity, then the four quadrants between the lagna, the nadir, the descendant and the meridian each cut into three. Those twelve are the middles of the bhavas and each bhava runs from midpoint to midpoint. A planet near a sign boundary can therefore sit in one sign but the next bhava, and the page says so for each such planet.

Shadbala

The six strengths in virupas, sixty to a rupa. Sthana bala adds the distance from deep debilitation over three, the dignity in seven vargas, the odd or even sign and navamsa, the kendra placement and the drekkana. Dig bala measures the arc from the planet's strongest cusp. Kala bala adds the day and night strength from the actual sunrise and sunset, the paksha strength, the third of the day, the lords of the year, month, weekday and hora, and the declination strength. Chesta bala is read from the motion class, Naisargika bala is fixed, and Drik bala is the aspects received. The required minimums are Suriyan 390, Chandran 360, Sevvai 300, Budhan 420, Guru 390, Sukran 330 and Sani 300. Two simplifications are stated on the page: the aspects are whole-sign, and a retrograde planet is scored as vakra without the days before it.

Shown on Jathagam.

The avasthas, the states of a graha

BPHS chapter 45 gives several schemes of avasthas, and Phaladeepika chapter 3 adds to one of them. They are worked out for the seven grahas from the Sun to Saturn.

Baladi, by age

The sign is cut into five parts of 6°. In an odd sign they run Bala, Kumara, Yuva, Vriddha and Mrita, the infant to the dead; in an even sign the other way round. Bala gives a quarter of the graha's results, Kumara half, Yuva all of them, Vriddha very little and Mrita none. A degree exactly on a boundary belongs to the later part.

Jagradadi, by wakefulness

Awake in its own, moolatrikona or exaltation sign, and full results. Dreaming in a friend's or a neutral's sign, and middling results. Asleep in an enemy's sign or in debilitation, and none. The friendship is the natural one, as BPHS states it for this scheme.

Deeptadi, by dignity and condition

One of seven sign states, from the dignity and the compound friendship with the sign's lord: Deepta when exalted, Swastha in its own sign, Mudita in a great friend's sign, Shanta in a friend's, Deena in a neutral's, Duhkhita in an enemy's and Khala in a great enemy's. BPHS names no separate state for debilitation, so it is given Khala, the worst. Four conditions can hold as well: Vikala, with a natural malefic (BPHS); Kopa, combust (BPHS); Shakta, retrograde; and Peedita, the loser of a planetary war (both Phaladeepika).

Sayanadi, the twelve activities

Sayana, Upavesana and ten more, from BPHS's formula: the graha's star times its number times its navamsa, plus the birth star, the ghatis of birth and the lagna, divided by 12. Commentators differ on "its navamsa"; its place 1 to 9 within the sign is used, with the two other readings available. The ghatis are counted from the sunrise of the birth day, the one in progress counting whole. BPHS divides each state again by the first syllable of the person's name; that is not worked out.

The upagrahas

The eleven sub-planets of BPHS chapter 3, which give no light of their own.

Five from the Sun

Dhuma is the Sun plus 133°20′. Vyatipata is 360° less Dhuma. Parivesha is Vyatipata plus 180°. Indrachapa is 360° less Parivesha. Upaketu is Indrachapa plus 16°40′, which always lands 30° behind the Sun, BPHS's own check.

Five from the hour

The day, sunrise to sunset, and the night, sunset to sunrise, are each cut into eight equal parts. By day the first part belongs to the weekday's lord and the rest follow in weekday order; by night the first belongs to the lord of the fifth weekday from it. The eighth part has no lord. The parts of the Sun, Mars, Mercury, Jupiter and Saturn give Kala, Mrityu, Ardhaprahara, Yamaghantaka and Gulika. Each is the degree rising at the start of its part, as BPHS says of Gulika; the middle or the end of the part can be chosen instead. A birth before sunrise belongs to the previous weekday's night.

Mandi

Kept apart from Gulika, as the Kerala texts keep it (Prasna Marga). It rises at a fixed ghati of a thirty-ghati day or night, set by the weekday: by day 26, 22, 18, 14, 10, 6 and 2 from Sunday to Saturday, and by night 10, 6, 2, 26, 22, 18 and 14. The ghati is scaled to the real length of the day or night. That puts Mandi in the second half of Saturn's part, a little after Gulika.

Bhava bala, the strength of the houses

After BPHS chapter 27, worked the way B. V. Raman's Graha and Bhava Balas works it, in virupas. Three parts are added for each house. First, the full Shadbala of the lord of the sign on the house's middle. Second, the house's dig bala. Each sign is of one kind: human, four-footed, watery or insect. Human signs are strongest in the 1st house, watery in the 4th, the insect sign Viruchigam in the 7th and four-footed signs in the 10th. Each kind is powerless in the opposite house, and gains 10 virupas for every house it stands away from it. Kadagam is taken as watery, as Raman takes it; some lists make it an insect sign.

Third, the aspects on the house's middle, graded by the degree (BPHS chapter 26), with Mars, Jupiter and Saturn's special aspects taken as full. The aspects of Jupiter and Mercury are added in full. Those of Venus and a waxing Moon add a quarter. Those of the Sun, Mars, Saturn and a waning Moon take a quarter away. The house middles are the Sripati ones. Some manuals also add or take away a flat 60 virupas for particular grahas in a house; that is not in BPHS and is left out.

Ishta and Kashta phala

From the BPHS chapter that follows Shadbala. With U the graha's Uchcha bala and K its Cheshta bala, both out of 60, Ishta phala is the square root of U times K. Kashta phala is the square root of (60 − U) times (60 − K). Some later manuals average the two instead; that is not what BPHS does. A graha leans auspicious when its Ishta beats its Kashta by a virupa or more, inauspicious the other way, and balanced in between. Both inputs are read from the Shadbala described in the section above, not worked out again. There the Sun's and the Moon's Cheshta bala is their Ayana bala; BPHS gives the Moon its Paksha bala instead, and that reading is available.

Graha yuddha, the planetary war

Only Mars, Mercury, Jupiter, Venus and Saturn fight, and only when they are within 1° of each other (Surya Siddhanta chapter 7; Brihat Samhita chapter 17). The Sun and the Moon never fight, and nor do the nodes. Venus wins whenever it is one of the two, as both texts say. Otherwise the planet further north in ecliptic latitude wins, the Surya Siddhanta's rule, with the latitudes from the live ephemeris. Only when no latitude can be had does the planet further along in longitude win. That is a modern convention, and the result says when it was used.

Shown on Jathagam.

The yogas are read on whole-sign houses from the lagna, and "the Nth from" a point counts that point as the 1st. The aspects are the whole-sign Parashari ones: every graha aspects the 7th, Mars also the 4th and 8th, Jupiter the 5th and 9th, and Saturn the 3rd and 10th. For these yogas the natural benefics are Jupiter, Venus, Mercury and a waxing Moon, after BPHS chapter 3. The shorter list the jathagam has always printed keeps its older habit of counting Mercury and the Moon as benefic in every case. "Afflicted" means debilitated or combust. The texts do not grade most yogas; the words weak, moderate and strong below are this site's stated convention.

Vipareeta raja yoga (Phaladeepika ch. 6)

Harsha, Sarala and Vimala, from the lords of the 6th, 8th and 12th. The lord must stand in one of the other two of those houses. Phaladeepika also allows it in its own house; that reading is available but not used by default. It is weak when that lord also rules the lagna or sits with the lagna lord. It is strong when a second of those lords joins it or exchanges signs with it.

Neecha bhanga, rule by rule

Every cancellation that holds for a debilitated graha is listed. From Phaladeepika chapter 7: its sign lord, its exaltation lord, or the graha exalted in its sign, in a kendra from the lagna or the Moon; and its sign lord aspecting it or sitting with it. From later South Indian practice, marked as such: an exchange with its sign lord; the graha exalted in that sign sitting beside it; and the graha itself in a kendra from the Moon. One rule is weak, two moderate, three or more strong.

Maha, Khala and Dainya (Phaladeepika ch. 6)

Two grahas each in the other's sign. If either of the two houses is the 6th, 8th or 12th, it is Dainya. Otherwise, if either is the 3rd, it is Khala. Otherwise it is Maha. The houses are the ones actually exchanged, not every house each graha rules.

The panchangam of the birth

BPHS asks for a shanti for birth on Amavasai, on Krishna Chaturdasi, in Vishti karana, in Vyatipata or Vaidhriti yoga, and in Gandanta. Gandanta is read by the pada: the last pada of Ayilyam, Kettai or Revathi, or the first of Magam, Moolam or Aswini. Some texts take only the last and first ghatis instead. Birth on Pournami is the one auspicious tithi (BPHS ch. 27). Siddha, Amrita Siddhi, Sarvartha Siddhi, Dagdha, Visha and Hutasana are read from the tables of Muhurta Chintamani chapter 1. The weekday runs sunrise to sunrise when the sunrise is known, and the civil weekday is used, and said, when it is not.

Kemadruma (BPHS ch. 37; Phaladeepika ch. 6)

None of Mars, Mercury, Jupiter, Venus or Saturn in the 2nd or 12th from the Moon. Five cancellations are tested: one of them with the Moon; the Moon in a kendra from the lagna; one of them in a kendra from the Moon; one of them in a kendra from the lagna; and Jupiter aspecting the Moon, which is later practice.

Gajakesari (Phaladeepika ch. 6)

Jupiter in a kendra from the Moon. BPHS also allows a kendra from the lagna; that reading is not used. It is weak when Jupiter is debilitated, combust or in an enemy's sign, and strong when Mercury or Venus joins or aspects it.

Chandra-Mangala (Phaladeepika ch. 6; Saravali ch. 15)

The Moon and Mars together in one sign. The two facing each other across the 7th is counted as the weaker form.

Adhi (BPHS ch. 37)

At least two of Mercury, Jupiter and Venus in the 6th, 7th and 8th from the Moon. All three is strong.

Amala (BPHS ch. 36)

The 10th from the lagna or from the Moon holding at least one benefic and no malefic.

Sunapha, Anapha, Durudhara, Vesi, Vosi, Ubhayachari (BPHS ch. 37 and 38)

Grahas in the 2nd, the 12th, or both, from the Moon, and the same from the Sun. Only Mars, Mercury, Jupiter, Venus and Saturn count. When both sides are occupied, only the combined yoga is named.

Budha-Aditya (Saravali ch. 15)

The Sun and Mercury in one sign. Mercury within 14° of the Sun, or 12° when retrograde, is combust, which weakens it.

Sakata (BPHS ch. 36; Phaladeepika ch. 6)

The Moon in the 6th, 8th or 12th from Jupiter. The Moon in a kendra from the lagna cancels it.

Lakshmi (BPHS ch. 36)

The 9th lord in a kendra, in its own or its exaltation sign, with a strong lagna lord.

Saraswati (Phaladeepika ch. 6)

Jupiter, Venus and Mercury each in a kendra, a trikona or the 2nd, with Jupiter in its own, its exaltation or a friend's sign.

Parvata (BPHS ch. 36)

Benefics in the kendras with no malefic there, and the 6th and 8th empty or holding only benefics. Or the lords of the lagna and the 12th in kendras from each other.

Kahala (BPHS ch. 36)

The lords of the 4th and 9th in kendras from each other, with a strong lagna lord. Or the 4th lord in its own or exaltation sign, joined or aspected by the 10th lord.

Each yoga comes with a sentence saying why it is or is not formed. A yoga the older list already carries is not listed twice.

Varshaphal

The Tajika annual chart is cast for the instant the sidereal Sun returns to its natal longitude, found by bisection to a fraction of a second. Muntha is the natal lagna advanced one sign per completed year. The year lord is the strongest of five candidates, the lords of the Muntha, the birth lagna, the year lagna, the sign of the Sun by day or the Moon by night, and the Trirashi lord, judged by the Panchavargiya bala of Kshetra, Uchcha, Hadda, Drekkana and Navamsa strengths. Eight Sahams are computed with their day and night forms, and the Mudda dasha runs the Vimshottari proportions over the 365.25 days of the year from the Moon's nakshatra lord in the year chart.

Ashtottari, Yogini and Chara

Ashtottari is a 108-year cycle of eight lords and Yogini a 36-year cycle of eight yoginis, both counted from the birth star. Chara is Jaimini's sign dasha, counted from the lagna. The page says when each is traditionally read. Their rules are set out under The other dashas, above.

KP

The zodiac is cut into 249 sub divisions, each nakshatra split in Vimshottari proportions starting with its own lord, so the first sub of Aswini is Ketu's 46′40″. Planets are read by sign lord, star lord and sub lord. The twelve cusps follow Placidus, by the semi-arc method iterated to convergence from the sidereal time, the latitude and the obliquity, then reduced to the sidereal zodiac. Significators are listed at the four levels KP readers use. The KP ayanamsa is available on the Settings page. The KP rules are set out in full two sections below.

Shown on Daily rasi.

The lunar birthday

A birthday kept by the Hindu calendar falls on the day the birth tithi runs at sunrise, in the birth lunar month. The month is amanta by default: new moon to new moon, named for the sign the Sun enters inside it. The purnimanta reckoning of the north only renames the dark fortnight, so the day is the same under both, and only the month's name changes.

When the birth month comes twice in a year, the nija month is used: the true one, which holds the Sun's sign entry. A person born in an adhika month keeps the nija month of the same name. A tithi that touches no sunrise at all is kept on the day it begins. A tithi that holds two sunrises is kept on the first, as the almanac keeps an observance. A month that straddles the new year can put the birthday in the next January, and a year can hold two.

Tithi Pravesha

The chart for the moment the Moon's distance from the Sun returns exactly to its value at birth, while the Sun is back in its birth sign. That is how Jagannatha Hora and P. V. R. Narasimha Rao's Vedic Astrology: An Integrated Approach define it. The Sun stays about thirty days in a sign and that distance repeats every 29.53 days, so a year holds one such moment and now and then two. The one nearest the Sun's exact return to its birth degree is taken, and the other is listed. The moment is found by repeated halving, to about a millisecond. The chart is cast for the birth place unless a place of residence is given, which is the usual practice.

Shown on Prashna and Year ahead.

The KP rules follow K. S. Krishnamurti's own Readers: Reader III (Predictive Stellar Astrology), Reader IV (Marriage, Married Life and Children) and Reader VI (Horary Astrology). KP is read in the Krishnamurti ayanamsa, and the Prashna page's KP chart uses it by default. On the other pages a chart is read in whatever ayanamsa it was cast in.

Subs and sub-subs

Each nakshatra is cut into nine subs in the Vimshottari proportions, starting with the nakshatra's own lord. That gives 243 subs. Six of the twelve sign boundaries fall inside a sub, and KP counts each of those subs twice, once in each sign, which is where 249 comes from. Each sub is cut again into nine sub-subs the same way, starting with the sub lord. So every point has a sign lord, a star lord, a sub lord and a sub-sub lord.

Placidus cusps

The 10th cusp is the midheaven and the 1st the ascendant. The 11th, 12th, 2nd and 3rd are the points that have travelled one third or two thirds of their own half-arc of day or of night. Each depends on its own declination, so it is found by repeated approximation. The classical recipe is five plain passes. For the 2nd cusp those passes swing back and forth, so the same step is damped by half and run forty times, until it settles. It then agrees with an independent solution to the last digit.

The four grades of significators (Reader III)

For every house: first, the planets in the star of a planet occupying the house, the strongest; second, the planets occupying it; third, the planets in the star of the house's lord; fourth, the lord itself. Occupancy is by the Placidus cusps, not by whole signs. Rahu and Ketu own nothing. Each stands in for the lord of the sign it is in and for the planets in that sign with it, and gives their houses (Readers III and VI).

The ruling planets (Reader VI)

At the moment of judgement: the lord of the day; the Moon's sign lord, star lord and sub lord; and the lagna's sign lord, star lord and sub lord. Reader VI names the first five, weakest to strongest, with the lagna's star lord the strongest; the two sub lords are later practice. The day runs from sunrise to sunrise at the place, so a question put before dawn belongs to the previous day's lord. A node in the sign or the star of a ruling planet, or in the same sign as one, is added as its agent, and counts as stronger than the planet it stands for.

Cuspal interlinks

For every cusp, its four lords and a chain from the sub lord: the sub lord's own star lord and its own sub lord, with the houses each reaches. Cusps whose sub lords are the same planet, or a planet in the chain, are linked: those matters come about together.

The cusp reading

The sub lord of the cusp that belongs to the question decides it. A planet gives the results of its star lord before its own, so the houses counted are the star lord's first and the sub lord's own second. More houses for the matter than against it is a yes. When the two sides balance exactly, the sub lord's own sub lord settles it: yes when it confirms, no when it withholds. When the houses against are more, the answer is no if that third link withholds too, and left open otherwise. A retrograde sub lord does not refuse the matter; it delays it until the planet turns direct.

Any other house takes the general rule of Reader III: the house itself and the 11th for it, the 12th from it and the 8th against it. For a lost article some KP writers read the 11th cusp instead of the 2nd.

Eclipses

Solar and lunar eclipses follow Meeus, Astronomical Algorithms chapter 54, from the lunation number: the mean phase, the corrections for the anomalies and the node, the test on the argument of latitude, gamma and u, and from those the kind of eclipse, total, annular, hybrid or partial for the Sun and total, partial or penumbral for the Moon, with the magnitudes and the semi-durations of the partial and total phases. The instants are converted to the place's local time. Visibility for a lunar eclipse is decided from the Moon's altitude through the contacts; for a solar eclipse only a rough regional statement is possible without the Besselian elements, and the page says so.

Moons, ingresses and stations

New and full moons are roots of the Sun and Moon elongation found by Newton's method. A planet's sign entry is a root of its sidereal longitude against the boundary, its station a root of its daily motion, and its combustion the crossings of its distance from the Sun against the traditional orb. Guru, Sani, Rahu and Ketu peyarchi are the sign entries of those bodies. Outside 1800 to 2050 the planetary tables are extrapolated and the page warns.

Maharashtra

The amanta months with Marathi names and the Shalivahana Shaka year from Gudi Padwa. Sankashti Chaturthi is read at moonrise and called Angarki on a Tuesday; Lakshmi Pujan follows the pradosha Amavasya; Vat Purnima, Vasubaras and Datta Jayanti read midday or pradosha, as the printed panchang does.

Bengal and Assam

Solar months from the sidereal sankrantis where the ingress day is the last day of the outgoing month. Bengal settles the ingress day with the before-sunset test, which reproduces the later Surya Siddhanta ingress the West Bengal panjikas use, so Poila Boishakh falls on 15 April; Assam takes the plain civil day, so Bohag Bihu falls on 14 April with Goru Bihu the day before. The Bangabda and Bhaskarabda years both count from 593 CE. Durga Puja days follow the sunrise tithi, Kojagari Lakshmi Puja and Kali Puja the night.

Punjab

The Nanakshahi calendar is fixed to the civil year: Chet 1 is 14 March, the first five months have 31 days and the rest 30, Phagun absorbs the leap day, and the year is the civil year less 1468. Vaisakhi is placed on the Bikrami Mesha sangrand, the day the Panth keeps, with the fixed Vaisakh 1 shown beside it; Guru Nanak's Gurpurab is the Kartik Purnima from the lunar scan.

Sri Lanka

Poya is the civil day on which the true full moon falls by Colombo time, named for the lunar month it closes, with Adhi on an intercalated month; the Buddhist era adds 543 and turns at Vesak. The gazetted list is computed from the older mean-motion almanac and can sit a day earlier than the true instant, which the page states.

Nepal

Bikram Sambat months begin on the civil day of the sankranti, the year is the civil year plus 57 from Baisakh 1, and Dashain runs from Ghatasthapana to Kojagrat Purnima with Fulpati, Maha Ashtami, Maha Navami and Vijaya Dashami marked; Tihar's five days follow the tithis from Kag Tihar to Bhai Tika.

Sevvai dosham is read in two house systems side by side. The Tamil and Kerala reading counts Mars in the 1st, 2nd, 4th, 7th, 8th and 12th; the North Indian reading counts 1, 4, 7, 8 and 12 and treats the 2nd as optional. Each is counted from the lagna, from Chandran and from Sukran, so six cells per person. Intensity rises when more than one reference point flags it or Mars is debilitated or in an enemy's sign, and eases with the classical cancellations: own or exalted sign, the house-and-sign exemptions, Guru's company or sign, Sani or Rahu's company, and Guru, Sani or Rahu aspecting Mars. When both people carry the dosha in the same system it is read as balanced; a strong dosha on one side against none on the other is flagged.

Nadi dosha is set aside when the two share a rasi with different stars, share a star across two rasis, have the same rasi lord or great friends as lords, or share a star lord. Bhakoot dosha is set aside when the rasi lords are the same or friends, or the pair is Mesham with Viruchigam or Rishabam with Thulam, the 6/8 pairs one graha owns at both ends. Rajju is graded by its part of the body: Siro strongest, then Kanta, Nabhi, Uru and Pada, with the milder readings for different padas, different ganas, or stars on opposite arms of the rajju noted but never used to cancel.

Prashna

The chart is cast for the instant the question is put, at the place it is put, and the Moon's placement from the prashna lagna is read from the traditional table. For a KP horary number from 1 to 249 the lagna is placed at the start of that sub's arc, the sidereal time that puts the ascendant there at the latitude is solved, and the Placidus cusps follow from it; the ruling planets are the day lord and the sign, star and sub lords of the Moon and the lagna at the moment of judgement. A yes or no answer reads the sub lord of the house the question belongs to, through its star lord first, against the houses that favour or deny that matter.

Jaimini

The chara karakas rank the seven planets by degree within sign, Atmakaraka first, with the eight-karaka variant counting Rahu from the end of its sign. An arudha pada is found by counting from a house to its lord and the same distance again, moving ten signs when it lands on the 1st or 7th from the house; A1 is the Arudha Lagna and A12 the Upapada. Argala comes from the 2nd, 4th and 11th, with the 5th secondary, and is obstructed from the 12th, 10th, 3rd and 9th; Ketu in the 3rd does not obstruct. Rasi drishti has movable signs aspect the fixed except the next, fixed aspect the movable except the previous, and dual signs aspect each other. Karakamsa is the navamsa sign of the Atmakaraka, read in the rasi chart.

Shown on Jaimini.

The Jaimini rules follow Sanjay Rath's translation of the Upadesa Sutras (Sagar Publications, 1997), cited by sutra number. Where a rule is Parashara's, it is cited to BPHS in R. Santhanam's translation. Most choices below have a living alternative in another school.

Argala, in full (Sutras 1.1.5–1.1.10)

Grahas in the 2nd, 4th and 11th from a house intervene in its affairs, and the 5th is a secondary argala. Grahas in the 12th, 10th, 3rd and 9th answer them. The obstruction holds when the obstructing house has as many grahas or more. At equal numbers, the side with more grahas exalted or in their own sign wins, and an even contest still counts as held off (1.1.8). Two or more malefics in the 3rd give an argala of their own (1.1.6). Ketu in the 3rd does not obstruct, as Rath reads 1.1.10.

Jaimini raja yogas

Every pair among the Atmakaraka, the Amatyakaraka, the Putrakaraka and the Darakaraka that is joined in one sign, sees each other by rasi drishti, or has exchanged signs. BPHS chapter 39 names the Atmakaraka with the Putrakaraka and the other karakas; Rath's commentary extends the union to these four and to all three ways of joining. A yoga with both in a kendra or trikona from the lagna gives its result most fully, and is marked strong.

Arudha yogas (Sutras 1.3; BPHS ch. 29–30)

Read from the Arudha Lagna. The Sun, the Moon or Venus in the 11th from it, or seeing it, is a yoga of wealth and standing. More grahas in the 11th from it than in the 12th means income beats expense. Malefics in the 3rd and 6th from it make a person bold and a winner against opposition; benefics there give a peaceable nature. Grahas in the 12th from it are expense: benefics spend on good causes, malefics waste. An empty 12th that no graha sees is money kept.

The Upapada and marriage (Sutras 1.4)

The Upapada is the arudha of the 12th house, where a Jaimini astrologer looks first for a marriage. Malefics in or seeing the 2nd from it, with no benefic there, warn of separation (1.4.2); a benefic in or seeing it cancels the warning (1.4.3). Its lord debilitated warns of the loss of the spouse (1.4.4); exalted, of more than one marriage (1.4.5). The Upapada in Mithunam is read as more than one marriage (1.4.6). The Darakaraka, and the grahas in the 7th from the karakamsa, describe the spouse.

The karakamsa reading (Sutras 1.2)

The grahas standing in the karakamsa sign are read by Sutras 1.2.14–1.2.22. The grahas that see it by rasi drishti bring the same significations from outside. The Sun and Rahu together there warn of danger from snakes, removed by a benefic's sight (1.2.23–1.2.24). The 12th from the karakamsa is the house of the end of life: a benefic there, above all an exalted one, gives a good world after this one, and Ketu there gives final release, most of all when the karakamsa is Mesham or Dhanusu.

Lifetime timeline

Every sign entry of Guru, Sani, Rahu and Ketu from birth to ninety years is found as a root of the sidereal longitude against the boundary, with retrograde re-entries kept so a stay a retrograde loop cuts in two is shown as it happened. The gochara for any date counts houses from the natal Moon and lagna, and each transiting planet carries the bindus of its Bhinnashtakavarga in the sign it occupies, five or more read as supportive, four mixed, three or fewer weak.

Sade sati

Sani in the 12th, 1st and 2nd from the natal Moon, the three phases called rising, peak and setting; Ashtama Sani in the 8th and Ardhashtama in the 4th. The dates come from Sani's exact ingresses, with retrograde dips joined into one span and flagged.

Lal Kitab

The chart is drawn with fixed houses, Mesham always the first, so a planet's house is its sign number. Each planet has a pakka ghar, exalted and fallen houses in Lal Kitab's own terms, aspects by its own table, sleeping planets and houses, the seven rin with the placement that raised each, and one short household upay per planet and house. The nodes' houses and aspects differ between commentaries; the common printed set is used and said so.

Nandi Nadi

Guru stands for the person, Sukran for the spouse, Sevvai for profession and brothers, Sani for karma, Budhan for learning, Suriyan for the father and Chandran for the mother; planets with Guru, opposite, in trine or in the 2nd and 12th are read as the person's traits, and the years when transit Guru conjoins or opposes natal Guru, Sukran, Sani and Sevvai are listed as the timing.

Shown on Transits.

Kakshya

Every sign is cut into eight kakshyas of 3°45′, ruled in turn by Saturn, Jupiter, Mars, the Sun, Venus, Mercury, the Moon and the lagna. A transiting graha gives its good only while the lord of the kakshya it is crossing gave it a bindu in that sign, in the graha's own Bhinnashtakavarga from the birth chart. This is Parashara's Ashtakavarga gochara, the rule Tamil almanacs print as kakshya vedha. The page shows all eight kakshyas of the sign, so you can see how far it is to the next good one.

Vedha

The classical table of good transit houses, counted from the birth Moon, each with the one house that cancels it (Brihat Samhita; Phaladeepika). A graha in a good house gives that good only if no other graha stands in the cancelling house. The Sun and Saturn never cancel each other, nor do the Moon and Mercury. Only the seven planets take part; Rahu and Ketu are outside the old table on both sides.

Murthi

When Guru, Sani, Rahu or Ketu enters a sign, the Moon's house from the birth Moon at that moment grades the whole stay. The 1st, 6th or 11th is gold (Swarna), the best. The 2nd, 5th or 9th is silver (Rajata). The 3rd, 7th or 10th is copper (Tamra). The 4th, 8th or 12th is iron (Loha), the poorest. The entry is found on the ephemeris to the minute, so the Moon's sign is the real one and not a table's. A re-entry after a retrograde loop counts as the entry.

The Sarvatobhadra chakra

A grid of 9 by 9 cells, drawn with East at the top. The outer ring holds the 28 stars, Abhijit included, Karthigai first on the East side. Inside it lie the twenty name letters, then the twelve rasis, then the five tithi groups with their weekdays, with the sixteen vowels in the corners. Each side's letters are the opening syllables of that side's stars, so a diagonal from a star runs through its own letter and its own rasi.

A transiting graha pierces every cell on three lines drawn from its star: straight across, and the two diagonals. That three-line rule is the Mansagari's and most almanacs'. The older rule by motion is available: straight in mean motion, forward when fast, back when retrograde, with the Sun, Rahu and Ketu piercing all three. A graha in one of the two padas that meet at a corner, such as Bharani's last and Karthigai's first, also pierces that corner's whole diagonal. Saturn, Mars, the Sun, Rahu and Ketu are malefic. Jupiter and Venus are benefic. The Moon is benefic while waxing, and Mercury unless it shares a sign with a malefic. A benefic piercing eases a malefic one on the same point.

The points of the birth that are read are the star, the first letter of the name and its vowel, the rasi, the tithi and the weekday. Reading the first letter from a name typed in English or Tamil is a guess at its sound, so the page lets you choose the letter yourself.

Shown on Rectify time.

A birth time moves three things that events can be read against. It moves the lagna, and with it every house lord. It moves the navamsa lagna. And through the Moon, which moves about half a degree an hour, it moves the balance of the Vimshottari dasha: a quarter of an hour shifts every later period by weeks. So a set of dated events fits some candidate times better than others. That narrows the time. It never proves it.

The lagna bands

The window is the recorded time plus or minus three hours, or the whole day when the time is not known. It never leaves the date of birth, because a family unsure of the hour is almost never unsure of the date. Every change of lagna, navamsa lagna, star and pada inside the window is found and pinned to the second. A birth time anywhere inside one band gives the same rasi chart.

The event score

Every candidate minute is cast afresh. For each event, the mahadasha, antardasha and pratyantara lords running at noon on its date are compared with the event's significators. These are the lords of the houses the event belongs to, counted from that candidate's own lagna; the natural karakas; the grahas in the event's main house; and Rahu or Ketu standing in a sign ruled by one of those lords. A marriage adds the lord of the 7th from the Moon and the lord of the navamsa lagna.

A significator scores 3 as mahadasha lord, 2 as antardasha lord and 1 as pratyantara lord. Then comes the double transit: Guru and Sani on the event date each add 1 when they stand in or aspect the main house, or the sign holding its lord. The best windows are the runs of candidates scoring at least 85% of the best score.

Kunda, sex and tattva

Three old checks from the Kerala and Tamil manuals are shown as a hint beside the events, never instead of them.

Kunda

The lagna's longitude times 81 should fall in the Moon's own star or in one of its two trines, the 10th and 19th stars from it. This is the rule the Kerala manuals print after Prasna Marga. It holds for about a ninth of any stretch of time, so it fine-tunes a window already chosen; it cannot choose one.

Sex

Brihat Jataka IV.11 reads odd signs and odd navamsas as male and even ones as female. Here the navamsas of the lagna and of the Moon both odd read male, both even read female, and one of each says nothing.

Tattva

After D. V. Subbarao's Jyotisha Siddhantamu (1970), from Jataka Phala Chintamani. From sunrise the five tattvas run Prithvi 6 minutes, Jala 12, Tejas 18, Vayu 24 and Akasha 30. The round opens with the tattva of the weekday's lord, and the next round runs the five backwards. Prithvi, Tejas and Akasha are male; Jala and Vayu are female. Other manuals start every day at Prithvi, or repeat the round without reversing it; this is one printed version.

Several windows can fit equally well. A wrong event date moves the answer. The significations are traditional and broad. Treat a rectified time as a narrowed window to take to the family astrologer.

A gem is recommended only for the lords of the 1st, 5th and 9th houses, only when that lord's Shadbala ratio is below one, and never when it also owns the 6th, 8th or 12th. The stone for an enemy of a stone already worn is flagged from the natural friendships, and the blue sapphire and the two shadow-planet stones carry the trial-period caution. Rudraksha from one to fourteen mukhi are listed with their planet and deity, and the wearing rules are the common ones: day, finger, metal, the hour, and the weight convention of one ratti per ten kilograms with a floor per stone. None of this is a prescription; the page says to consult the family astrologer.

The temple finder carries 253 temples with the planet, dosham or wish each is visited for, the deity, usual pooja hours and notes: the Navagraha temples of the Kaveri delta, the six abodes of Murugan, the five-element sthalams, the Ashta Veeratta, the twelve Jyotirlingas, both Char Dhams, the Ashtavinayak, the Shakti Peethas, the pitru tirthams and the major shrines of Kerala, Karnataka, Andhra, Telangana, the north, Sri Lanka and Nepal. Nearest is by great-circle distance from the place you give; the suggestions for a chart come from its weak or afflicted planets and its doshams. Coordinates are to the town, not the gopuram, and the hours are a guide to check before travelling.

The week reads the Moon's house from the rasi day by day, houses 1, 3, 6, 7, 10 and 11 good and 4, 8 and 12 asking for care, the 8th being Chandrashtama, with the Sun, Budhan, Sukran and Sevvai of the week beside it. The month reads the Sun's house with the sankranti date if it changes, the mid-month houses of Budhan and Sukran, Sevvai, Guru, Sani and Rahu, the Chandrashtama dates, Pournami and Amavasai, and one line for each of health, money, family and work from the house of that area's karaka. The year reads Guru, Sani, Rahu and Ketu through the year with their peyarchi dates and a reading per quarter. Every sentence is a house-by-planet table written in plain words, without fatalism or prohibition.

Shown on Jathagam, Porutham and Report.

A chart in five sentences

Written for the family reader who wants to know what a chart says before reading the tables underneath. The five are the lagna and its lord, the Moon's star and rasi, the strongest graha, the running dasha and bhukti, and one caution or the plain absence of one. Every fact in them comes from the engine: the sign, the star, the graha, the period, the dosham and the dates. Only the character lines come from a table, keyed by what the chart holds. The strongest graha is chosen by Shadbala when the time of birth is known, and by dignity alone when it is not. Without a time, the Moon's rasi stands in for the lagna.

A match gets three sentences: the score, the two checks that can end a reading on their own (Rajju and Vedha), and a second opinion from the Ashta Koota and Sevvai dosham. The names follow the language select; the sentences stay in English. The wording is the traditional leaning of a placement, never a verdict on a person or a prediction.

The festival pages

Each of the 255 festivals and observances has a long form. It gives the story or the meaning, the hour of the main rite in plain words, the puja as steps a household can follow, the things to have ready, what is cooked, what is left alone, how each of the eleven traditions keeps the day, a greeting, and the mantras that go with it. 232 of them carry the full puja and food; the rest carry at least the meaning, the timing and what is avoided. Of the 255, 51 are the same day under another tradition's name.

The voice is a family elder's: plain English, with the reason beside the rule. Where traditions differ, the page says so rather than choosing. Nothing is quoted from scripture: a mantra is named and links to the mantra library. The family's own custom and the temple's own calendar always come first.

The match report

A printable document from the porutham page's two people: charts, the ten poruthams, the 36 points, the chart checks and verdict paragraphs written from the data in plain language, framed by a kolam. Save as PDF uses the browser's print.

Build a report

The astrologer's version of the same page. Choose the subject: a saved client, the person on the jathagam page, or the pair on the porutham page. Tick the sections, choose the language and the chart style, and print. Each section is worked out only when it is ticked, from the same engines the jathagam page uses. A section that cannot be drawn, for want of a birth time, says why under its heading.

Saved horoscopes

Kept on the device, and laid out for an astrologer's client list. Each person can carry tags, notes and a history of consultations. Birth details can be brought in from a Jagannatha Hora .jhd file, from text copied out of another program or your own notes, or from this app's own export. A person missing coordinates is completed from the place list when the town is in it, with a warning. Anyone already saved with the same birth details is updated rather than added twice.

Reminders

Rahu kaal, Nalla neram, the monthly vratams and chosen festivals become alerts. While the app is open they fire on time. A closed browser cannot promise delivery on its own, so there are three more routes: push reminders through the optional server (see the next section), the Android and iOS apps, which hand the list to the phone's own scheduler, and a year of alarms written into a calendar file, which every phone honours.

Transfer

Saved horoscopes move between phones as QR codes, encoded by the app itself, or as a pasted code or a file. Nothing passes through a server.

Share as image, and read aloud

A share button draws a picture card, 1080 by 1350 pixels: the day's panchangam, a match score, a chart, a festival, a month, the best muhurtham days or a rasi's day. The card is always in the light colours, because it lands in other people's chats. On a phone it goes to the share sheet; elsewhere it is saved as a file. Read aloud uses the voices the phone or browser already has, in the language chosen where a voice exists. The mantra library reads Sanskrit with a Hindi voice from the Devanagari, and offers a Tamil voice from the Tamil script as the second choice.

Learn, glossary and guides

Fourteen lessons run from what a jathagam is to reading this app's jathagam page, each with a diagram, a short quiz and a link into the real tool. Every technical word in them opens its glossary line in place. The glossary holds 408 words, each with its script form and the page it is used on. The Guides page walks through five tasks step by step: a wedding date, a baby's name, a day to travel, a griha pravesam, and a business or new job.

Offline and installed

A service worker caches the whole site, so it works with no network, and the manifest lets a phone install it as an app. The long scans, a calendar year, a muhurtham range, a year of sky events, run in a background worker so the page never freezes; on a browser without workers they run in short slices instead.

Search, welcome and diagnostics

Search covers the tools, the year's festivals with dates, the glossary, the lessons, the mantras, the Vastu rooms, the baby names and this page, all looked up on the device. First run asks for a language, a place and a first horoscope. Errors are logged on the device and can be exported from the Saved page; the log is never sent anywhere.

Shown on Account and Ask.

The app is complete without an account. Every chart and almanac is computed on the device, and saved horoscopes stay in its storage. Nothing about a person leaves the device unless you sign in, or turn on one of the features below. The server is PocketBase, run by whoever hosts the site.

Accounts and sync

An account is an email address and a password. Signed in, the saved horoscopes and the reminder settings are copied to the server, and from there to every device signed in with the same email. Every record carries the time it was last changed. A sync pulls what the server has changed since this device last synced, pushes what this device has changed, and the later change wins, record by record. A deleted person leaves a tombstone, a note of the id and the time of deletion, so the deletion reaches the other devices too. Erasing the account removes the saved people, the reminder settings, the questions and answers, and any push subscription linked to it from the server, in one step.

Push reminders

The only way a browser can raise an alert with the app closed. No account is needed: the device makes up its own id and secret, and the server keeps only a fingerprint of the secret. The device works out the next 60 days of reminders itself and sends only their titles and times, at most 300. The server never computes a panchangam. It sends each reminder at its time, and drops one more than six hours late, since a Rahu kaal alert for a window that has already ended is noise.

The question board

Questions about a chart, a date or a custom, put to the site's astrologers. A question can be public or private; a private one is read only by the asker and the astrologers. An astrologer's answer carries a mark, and other readers may answer too. The board lives on the server, so it needs a connection.

Corrections and feedback

A temple timing that looks wrong can be sent as a correction from the Temples page, and the Search page has a box for anything wrong or missing. Only what you type is sent, with the page it came from; the Search page adds the word that was searched for.

The Android and iOS apps

The same site inside a native shell, computing everything on the phone as the website does. The one difference that matters is reminders: the phone's own scheduler raises them on time with the app closed and no network.

Names and the interface can be read in English or in twelve Indian languages: Tamil, Telugu, Kannada, Malayalam, Hindi, Marathi, Gujarati, Bengali, Odia, Punjabi, Sinhala and Nepali. Hindi, Marathi and Nepali share the Devanagari script. The select changes the script alone, never the arithmetic, and a name with no form in the chosen script falls back to the Latin transliteration rather than showing nothing. Each native-script name is marked with its language so a screen reader and the browser's font picker both handle it correctly. Every language carries the 27 stars, 12 rasis, 9 grahas, weekdays, tithis, yogas, karanas, lunar and Kerala months, the sixty year names and about 180 interface words, in that language's own almanac usage rather than a transliteration of another.

The longer prose stays in English for now: the chart summaries, the lessons, the festival pages and this page. The glossary gives each word's script form beside it. Read aloud speaks the chosen language where the phone or browser has a voice for it. The mantras are printed in Devanagari, in Tamil script and in IAST, and the reader's own script is shown first.

Tamil

The Tamil solar calendar, the ten poruthams and the Tamil month and star names.

Malayalam

The Malayalam solar months and the Kerala festivals, with the Kollam year.

Telugu

The amanta lunar months, the sixty samvatsaras and the Andhra and Telangana festivals.

Kannada

The same calendar as Telugu, written in Kannada, with the Karnataka reading where the two traditions keep a festival on different days.

Hindi, Marathi, Gujarati, Bengali, Odia, Punjabi, Nepali, Sinhala

The purnimanta North Indian months with the Vikram year; Maharashtra's Shalivahana Shaka year; the Bengali and Assamese solar years; the fixed Nanakshahi months of Punjab; the Nepali Bikram Sambat; and the Sri Lankan Poya days. Sinhala names use the island's own lith vocabulary rather than Sanskrit.

Which matching system goes with which tradition

Kerala's pathu porutham is the same ten checks as the Tamil system on this site, read in the same order and with the same weights: Dina, Gana, Mahendra, Stree Deergha, Yoni, Rasi, Rasi Adhipathi, Vasya, Rajju and Vedha, with Rajju and Vedha the two that can end the reading on their own. The Malayalam names differ, the rules do not, so the porutham page serves both.

Telugu and Kannada families ask instead for the Ashta Koota, the eight kootas out of 36 points set out above: Varna, Vashya, Tara, Yoni, Graha Maitri, Gana, Bhakoot and Nadi. Nadi dosha is read there the way Rajju is read in the south, as a reason to stop. Both readings are shown on the porutham page for every pair, so a family that uses one can still see what the other says.

Numerology is not astronomy and nothing here depends on the ephemeris. It is included because it is asked for. Throughout, 11, 22 and 33 are master numbers and are kept whenever a running total lands on one instead of being reduced further.

Life path

The year, the month and the day are each reduced to a single digit on their own, the three results are added, and that sum is reduced once more.

Birth day number

The day of the month as it stands, shown together with its reduction.

Expression and Chaldean name numbers

Two letter tables. The Pythagorean table runs A to I as 1 to 9 and then repeats. The Chaldean table is the older one and never assigns the value 9 to a letter. Spaces, punctuation and case are ignored.

Soul urge and personality

The same Pythagorean values applied to the vowels alone for the soul urge, and to the consonants alone for the personality.

The compound number, the total before it is reduced, is kept and shown with its traditional Chaldean meaning, since that is where most of the reading sits.

Boundaries. The positions are good to about an arc-second for the planets and the Moon, which is far finer than a sign, a star or a pada needs. What is not that fine is the birth time: four minutes of clock moves the lagna a degree, and a Moon within half a degree of a star boundary still turns on whether the recorded time is right. The pages say so when a position sits that close. In that case the printed horoscope or the family astrologer decides, not this site.

Time of birth not known. If you mark the time as unknown the chart is computed for noon, and the page shows where the Moon stood at the start and at the end of the day, and whether the star or the rasi changed in between. The lagna, the houses and everything read from them are not meaningful without a time, so treat them as a placeholder rather than a reading.

Years far from now. The planetary series are sized for 1750 to 2250 and hold usefully from 1000 to 3000; the Moon's series is sized for 1900 to 2100; Delta T beyond the measured years is a fit. Dates inside 1800 to 2200 are accepted without comment. Outside that the positions are extrapolations, and any page using them says so.

Place and time zone. Sunrise, sunset, the eight-part windows, the lagna and everything built on them depend on the coordinates and the time zone you enter. A rough place gives a rough sunrise, and the wrong time zone shifts everything by whole hours.

The rules themselves. Traditions differ, and the choices made here are written down above rather than hidden. Whether the 2nd house counts for Sevvai dosham, which ayanamsa is used, which tithi convention fixes Vijayadasami, which school's Narayana dasha, which reading of Mandi or of a yoga: each of these moves a result, and a family astrologer may use another convention in good faith. Take these pages as a first filter and a way to see the working, then confirm the reading with the family astrologer before anything is decided.

A rectified time. Rectification narrows a birth time to a window that fits the events given. It does not prove the time. Several windows can fit equally, and one wrong event date moves the answer.

What stays on this device. Without an account, everything you enter stays in this browser's storage, and clearing the site's data removes it. With an account, the saved horoscopes and the reminder settings are also kept on the server you signed in to, and erasing the account removes them there. Push reminders send only the reminder titles and times. A question, a correction or feedback is sent only when you press send.