Every calculation this tool can run

The catalogue above lists every calculator and what each one asks for. This long read goes underneath the list: the classical texts each family comes from, the one astronomical calculation they all share, what each level of birth detail actually unlocks, how to read the different kinds of answer a calculator can give (a refusal included), and what a few minutes of error in a birth time does to each of them. It is a map of the whole set; each calculator's own page carries its detailed method.

Every number below was produced by running the code that serves these pages on a sample birth chosen for this page - 11 December 1989, 05:10 IST, Jaipur - evaluated on 5 October 2026, with nothing stored. It is not a real person. Where the engine declines to produce a number, this page says so as well.

One sky under every astrology calculator

Brihat Parashara Hora Shastra sets the frame in a few lines (Ch. 3, Sl. 4-6): the grahas are the bodies that move through the nakshatras; the zodiac holds 27 nakshatras beginning with Ashvini, and the same belt is divided into 12 rashis beginning with Mesha; the rashi rising in the east is the Lagna; and results are judged from the Lagna and the grahas together. Sl. 8-9 adds the instruction every calculator here depends on: take the positions of the grahas for the given time by Drikganit - computation that agrees with observation - and find the Lagna from the rising durations of the signs at the place of birth.

In the code that instruction is one function, computeChart, and every astrology calculator on this page calls it before doing anything else. It turns the birth instant into a Julian Day, computes tropical longitudes, subtracts the ayanamsa to get sidereal ones, and describes each point by sign, degree within the sign, nakshatra, nakshatra lord and pada. The calculators differ only in what they do with that one chart, which is why two of them cannot disagree about where your Moon is.

This is not Swiss Ephemeris, and no page here claims it is. The project's rules document names Swiss Ephemeris as the intended future source of truth and lists the checks any replacement must pass; the methodology page says the same in public, and the sources page lists the books. The Ayanamsa calculator prints the tropical-to-sidereal offset for any date: 23.7127 degrees on 11 December 1989 and 24.2266 on 5 October 2026.

Three conventions are fixed across the whole set. Houses are whole-sign: the rising sign is the 1st house and the next sign the 2nd. Rahu is the Moon's mean node everywhere. A graha is retrograde when its apparent longitude falls across the day surrounding the birth instant; Rahu and Ketu are always marked retrograde, the Sun and Moon never. Combustion uses fixed distances from the Sun: Moon 12 degrees, Mars 17, Mercury 14, Jupiter 11, Venus 10, Saturn 15.

The input ladder: what each birth detail unlocks

Each card above carries a short line saying what the calculator asks for. Behind it is one field in the catalogue, checked on the server before anything is computed. It helps to see the levels as a ladder: each rung adds one fact about the birth, and each fact unlocks a family of calculations that cannot be done without it.

Eight of the birth-date calculators cast the sky, so they also accept an optional time and place: Moon Sign, Sun Sign, Nakshatra, Moon Phase, Vimshottari Dasha, Sade Sati, Ashtama Sani and Gochar. Without a time the chart is cast at 12:00 on the birth date, the midpoint of the unknown day. Without a place or timezone the clock is taken as IST and the result says the timezone was assumed. The numerology calculators never ask for a time: they read the calendar date alone, and a time field there would collect personal data for nothing.

A missing rung is not treated as an error. Ask the Lagna calculator for 11 December 1989 with no time and the server answers successfully, with the result marked unavailable, the missing item named as the birth time, and a sentence explaining that the Ascendant needs both a time and a place, so no houses are shown in place of estimated ones. Add 05:10 but no place, and the missing item becomes the birth place. Only malformed input is rejected outright: 31 February is refused as not a real calendar date, a birth date before 1900 or in the future is refused, a Kua request without male or female is refused, and a Muhurat request must name one of its six activities.

The name-based calculators add one more refusal. They value the letters A to Z, so a name typed only in Devanagari comes back unavailable with a request to write it in Latin letters. The engine does not transliterate it for you, because these numbers are a function of spelling - Aarav and Arav differ - and choosing a spelling would be choosing the answer.

What does a missing time cost? It was measured. For every date from 1 January 1950 to 31 December 2009 - 21,915 dates, read on IST - the date-only calculators were run and the two ends of the day compared: 00:00 and 23:59, which every date-only result prints beside its noon reading.

So a birth date alone settles the Sun sign on about 29 dates in 30, the Moon sign on a little over half, and the Moon's nakshatra almost never - which is why those pages print the day's range in place of a single answer presented as certain. On the 912 dates where one nakshatra held all day, the dasha calendar at the two ends of the day still differed by nearly the whole first period, between 5.3 and 19.6 years, because the Moon had crossed almost the entire nakshatra in between. What an unknown birth time actually costs goes through the consequences one reading at a time.

Chart and signs: the chart, taken apart

The first group is the chart itself in pieces. Birth Chart is the whole of it and runs on its own tool page. Lagna returns only the Ascendant and the twelve whole-sign houses. Moon Sign (the rashi), Sun Sign and Nakshatra each return one point with its sign, degree, nakshatra and pada. Moon Phase reads the tithi: the Moon's distance ahead of the Sun cut into thirty steps of 12 degrees, the first fifteen Shukla and the rest Krishna. Nakshatra Sub-Lord divides a nakshatra's 13 degrees 20 minutes among the nine Vimshottari lords in proportion to their years. If the difference between a rashi and a star sign is new to you, start with the Moon, the nakshatra and a 24-degree disagreement.

The sub-lord page is a good example of how far a citation is allowed to stretch here. BPHS gives the lords and their years (Ch. 46, Sl. 12-15) and the proportional division of a period (Ch. 51, Sl. 1-2); it never divides a nakshatra's arc this way. The page therefore states that it extends the time rule to arc, that it uses the Lahiri ayanamsa and is not Krishnamurti Paddhati, and prints for every point how many arcminutes separate it from the next boundary. For the sample, the Moon at 1.54 degrees of Taurus is in Krittika with Jupiter as sub-lord, 87.42 arcminutes short of the next sub. The Ascendant's sub-lord is the Sun with 6.13 arcminutes in hand, which at that morning's rate of rising - 0.22 of a degree a minute - is under half a minute of clock time. The sub-lord article explains why that margin is the number to read first.

Divisional charts: fifteen rules from one chapter

BPHS Ch. 6 (Sl. 2-4) names sixteen divisions of a sign: the Rashi itself and fifteen finer ones, from Hora to Shashtiamsa. Ch. 7 (Sl. 1-8) says what each is consulted for. The catalogue carries all fifteen, each computed by the rule in its own sloka. The pattern is the same throughout: divide the 30 degrees of the sign a point occupies into equal parts, find the part its degree falls in, and count that many steps from a starting sign the text specifies.

Two of the fifteen do not return a twelve-sign wheel, because the text does not define one. Hora resolves every point to the Sun's half or the Moon's. Trimshamsa gives a ruling planet for a span of degrees and no rule for which of that planet's two signs a point would occupy, so the Trimshamsa page returns lords and nothing more. The rest return positions, houses counted from the varga's own Lagna, and a list of points that are vargottama - in the same sign as in the birth chart. The most used are Navamsa D9 and Dashamsa D10; the Navamsa article explains why a varga needs the birth time to the minute. The measured figures are further down this page.

Planetary strength: three ways of counting

BPHS Ch. 27 defines Shad Bala as six sources of strength - positional, directional, temporal, motional, natural and aspectual - worked out for the seven grahas from the Sun to Saturn, the nodes excluded, in units called Virupas with several sub-parts each. The Shad Bala calculator is a simpler instrument, and its code says so: a 20-point score per graha built from the same six components (position 0-10, aspect 0-3, direction 0-4, and natural rank, motion and time 0-1 each), following a condensed formula the code attributes to Kannan's handbook (Ch. VI), with each place where it interpolates marked. It bands the total as Strong at 13 or more and Weak at 7 or less. Read it as a consistent ranking of the seven grahas within one chart. It is not the classical Virupa total and should not be set beside Rupa figures from other software.

BPHS opens its Ashtakavarga chapters (Ch. 66, Sl. 1-6) with a frank admission: the general rules for judging grahas and houses pull against one another, so a method is wanted that an ordinary reader can apply without contradiction. The method is a count. Each of the seven grahas gives a point, a bindu, to certain houses counted from eight reference points - the seven grahas and the Lagna - and the points are added per house. The Ashtakavarga calculator returns each graha's own table and the combined Sarvashtakavarga, and it checks itself: the twelve combined totals must add up to 337 whatever the chart, and the result reports whether they did. For the sample they run 33, 26, 26, 23, 27, 30, 28, 28, 24, 27, 33 and 32 from the 1st house to the 12th, which is 337. The same page then applies the Trikona reduction of Ch. 67.

Vimshopaka Bala asks a different question: how well placed is a graha across all sixteen charts at once? BPHS Ch. 7 (Sl. 21-25) gives the weights - 3.5 for the Rashi, 4 for the Shashtiamsa, 3 for the Navamsa, 2 for the Shodashamsa, 1 each for Hora, Drekkana and Trimshamsa, and half a point for each of the other nine. They total 20, and the engine refuses to load if its table does not. How much of each weight a graha earns is this app's own stated choice: its dignity in that chart, on the same 0-10 scale Shad Bala uses, so the two strength pages cannot contradict each other about dignity. Sl. 26-27 reads the total in steps at 5, 10 and 15, and the engine cuts its four bands at the same three numbers. In the sample the two methods agree at the bottom but not at the top. The Moon, exalted in Taurus, leads Shad Bala with 14.08 of 20 but scores 11.06 on Vimshopaka, where Mars leads with 11.50; Jupiter, retrograde in Gemini, is lowest on both, at 4.83 and 4.50.

Dasha periods: three kinds of calendar

A dasha is a calendar: it divides a life into dated periods, each belonging to a graha or a sign. BPHS Ch. 46 (Sl. 2-5) lists many kinds and calls Vimshottari the most suitable for people in general. Sl. 12-15 gives its nine lords and their years, 120 in all, and Sl. 16 the rule for the balance left at birth, taken from how far the Moon has travelled through its nakshatra. The Vimshottari Dasha calculator follows those slokas and returns the full timeline, the period running today and its nine sub-periods. What a Mahadasha actually is and Antardasha and Pratyantardasha explain how the levels nest, and the Timing feature turns the same timeline into dated phases.

The same chapter attaches a condition to each of its other nakshatra-based systems. The Alternate Dashas calculator computes all nine of them - Shodshottari, Dwadashottari, Ashtottari, Panchottari, Shatabdik, Chaturashiti-sama, Dwisaptati-sama, Shastihayani and Shat-trimshat-sama - with Kala Chakra beside them, and, since each condition is something the chart already contains, evaluates it instead of merely repeating it. For the sample Shodshottari applies, a night birth in the bright fortnight, the case Sl. 23 names, and so does Ashtottari: Rahu is in Capricorn with the Ascendant lord Venus, a Kendra from it, and not in the Ascendant. Shat-trimshat-sama applies as well: a night birth with the Ascendant in the Moon's Hora. The page shows the facts each verdict was read from. Ashtottari and Shastihayani count Abhijit as a 28th nakshatra, read from the Moon's longitude as Ch. 46 Sl. 21-22 defines it; Shastihayani's sloka gives no balance rule and its table leaves out Chitra; both are taken from a published reference outside BPHS (Sanjay Rath) and flagged as such.

Chara Dasha is a different kind of clock. Its periods belong to signs, not grahas. The order starts at the Ascendant sign and runs forward when the sign in the 9th house is odd-footed and backward when it is even-footed, and each sign's length is the count from it to the sign its lord occupies, less one, with a lord in its own sign giving twelve years, a year more for an exalted lord and a year less for a debilitated one. Scorpio counts to Mars or Ketu and Aquarius to Saturn or Rahu, whichever BPHS's strength tests favour. The sample has Libra rising and Gemini in the 9th, so the sequence runs forward: Libra 3 years, Scorpio 8 (Mars sits in Scorpio itself, so the count goes to Ketu in Cancer), Sagittarius 6, and on to a total of 71 years, with Taurus running from December 2025 to December 2033. The page states its open points openly: where the sloka is ambiguous the engine follows K.N. Rao's school, K.N. Rao and U.K. Jha themselves omit the exalted/debilitated year, and BPHS's own sub-period order (Ch. 51 Sl. 6-12) is not applied.

Dosha, yogas and transits: reported as found

Three of these read the present sky against the natal Moon. Advanced Predictive Astrology, in its chapter on transits (pp. 311-313), defines Sade Sati as Saturn's passage through the 12th, 1st and 2nd signs from the Moon, recurring about once in thirty years, and records a variant that measures 45 degrees either side of the Moon instead. The Sade Sati calculator uses the sign rule and names the phase - rising, peak or setting. Ashtama Sani, from the same chapter, covers Saturn in the 4th and 8th from the Moon. Gochar extends the idea to all nine grahas counted from the Moon sign. On 5 October 2026 Saturn stood at 16.71 degrees of Pisces, retrograde - the 11th from the sample's Taurus Moon. Neither Saturn period was running, and Gochar marks the 11th from the Moon as favourable for any graha.

Mangal Dosha is a house test: Mars in the 1st, 2nd, 4th, 7th, 8th or 12th from the Lagna, graded Moderate in the 7th or 8th and Mild elsewhere, which is why it needs the birth place. The sample's Mars is in the 2nd, so it is present and Mild. Kaal Sarp Dosha is pure geometry - are all seven grahas on one side of the Rahu-Ketu axis? - and none of the searchable texts in this app's library names it at all. The page therefore applies the rule as commonly practised, returns each graha's angular distance from Rahu, declines to attach the twelve popular type names, and re-tests the verdict against the true node to show whether the choice of node decides it. The sample is not a Kaal Sarp chart: the Moon and Jupiter are on one side of the axis and the other five on the other. The background to both is in Mangal Dosha: what it is and is not and Kaal Sarp Dosha explained.

The Yogas calculator tests the chart against named combinations drawn from BPHS, Saravali and Advanced Predictive Astrology and returns the ones present, with the grahas that form them. It found six in the sample, among them Sunapha - any graha but the Sun in the 2nd sign from the Moon (Saravali Ch. 13, Sl. 1), here Jupiter in Gemini. A yoga being present is a statement about geometry; how common each one is, and how little the name alone tells you, is the subject of what a yoga in your chart means.

Jaimini: the same chart by other rules

BPHS Ch. 29 to 33 describe a second toolkit, usually called Jaimini's, that reads the same chart by different rules. Char Karakas ranks the seven grahas by how far each has travelled through its sign: the one with the most degrees is the Atma Karaka, the next the Amatya Karaka, and so on (Ch. 32, Sl. 3-17). The text itself records a rival view that counts Rahu as an eighth; the engine uses seven and says so. Karakamsa is the Navamsa sign of the Atma Karaka (Ch. 33, Sl. 1). Arudha Lagna and the twelve Bhava Padas count from a house to its lord and the same distance again, with the two exceptions of Ch. 29, Sl. 4-5. Argala tests which houses receive support from grahas in the 2nd, 4th and 11th from them, against obstruction from the 12th, 10th and 3rd (Ch. 31, Sl. 2-9).

In the sample the Sun, at 25.20 degrees of Scorpio, is the Atma Karaka, and Mars, at 1.30 degrees of the same sign, the last of the seven. The Sun's Navamsa is Aquarius, so the Karakamsa is Aquarius; the 12th from it is Capricorn, ruled by Saturn. The 12th from Karakamsa page stops there on purpose. BPHS (Ch. 33, Sl. 63-74) reads worship from the grahas occupying that sign, never from its lord, so the page reports the occupants in both the Navamsa and the birth chart, reports the lord as a structural fact, and leaves the deity field empty with the reason given. The Ishta Devata question explains why. The passages in these chapters that predict a spouse's illness or the manner of a death are not carried into any calculator.

Panchang and timing: where the day begins

Five calculators describe a day and not a person, and read no birth record at all. Panchang gives the tithi and the day's divisions; Choghadiya the eight daytime and eight night-time windows; Rahu Kaal one eighth of the daylight, chosen by weekday; Hora the twenty-four planetary hours. What matters most is where the day starts. Given a place, the engine computes true local sunrise and sunset and cuts every window from them: on 5 October 2026 in Jaipur that is sunrise at 6:21 AM and sunset at 6:09 PM, with Rahu Kaal from 7:50 to 9:18 AM. Given no place there is no sunrise to take, so the day is a fixed 06:00 to 18:00 IST and the same Rahu Kaal prints as 7:30 to 9:00 AM. Every result carries a line saying which frame was used. Where the Sun does not both rise and set on a date - polar day or night - the result says so and falls back to the fixed clock; it does not invent a sunrise.

Muhurat is the one timing calculator that needs your full birth record, plus one more choice: which of six activities the moment is for. It samples three 90-minute windows a day for the next thirty days and scores each from several independent factors - the Moon's nakshatra against a list favoured for that activity, the house the Moon is transiting in your chart, the tithi and fortnight, the weekday, Rahu Kaal and your Personal Day number - then returns the three highest with the reasons beside each score. Its windows are printed in IST on the fixed-clock day, because the place where you will act is not known to it. Varshaphal casts a new chart for the moment the Sun returns to its exact birth longitude - 11 December 2025 at 10:45 AM IST for the sample - and reports the Muntha and the candidates for lord of the year. It does not crown one, because the classical selection needs a five-part strength table this engine does not have. Prashna, the chart of a question's moment, follows Daivajna Vallabha and runs only inside the signed-in app; its page here describes it.

Matching: two Moons, and a grid

Kundli Matching and Love Compatibility are one engine with two framings, and they run on the match tool because they need two people and the ordinary calculator form collects one. The engine is Ashtakoot, the 36-point scheme of eight kootas: Varna 1, Vashya 2, Tara 3, Yoni 4, Graha Maitri 5, Gana 6, Bhakoot 7 and Nadi 8. All eight are read from the two Moons, four from the Moon sign and four from the nakshatra, so a birth place changes nothing and a birth time matters only through the Moon. When either Moon changes nakshatra or sign during its birth date, the result is marked provisional and names the kootas, and the points, that rest on the unsettled Moon.

One limit is written into the engine itself. None of the texts in this app's library - BPHS, Saravali, Bhrigu Sutras, Advanced Predictive Astrology, Daivajna Vallabha - contains the Ashtakoot point tables, so the scheme is applied as commonly practised, and for three kootas (Bhakoot, the Gana list and Graha Maitri) the code follows published Kundli-matching references where they agree, named in its header, since no text in the library has them. Varna appears here only as the name of the first koota, a classification of Moon signs; it says nothing about any person. Chinese Destiny Grid is a separate, number-based comparison: each birth date is reduced to a Destiny Number and the pair is looked up in a twelve-by-twelve grid of grades A to D from Numerology Masters Notes (p. 179). The sample's 5 against the 1 of a 23 March 1991 birth returns grade A; with no second date the page returns only your own number.

Numerology: several systems, kept apart

The numerology group is thirteen calculators drawn from several books, and the catalogue keeps the systems apart instead of blending them. All of them read the calendar date exactly as typed - a 02:00 birth is not moved to the previous day by a timezone conversion - and none takes a birth time.

For 11 December 1989 the core numbers are Mulank 2 (11 reduces to 2) and Bhagyank 5 (the digits total 32). The Lo Shu grid holds four 1s, two 9s, one 2 and one 8, leaving 3, 4, 5, 6 and 7 missing and the whole emotional plane (3-5-7) empty. The Power of Numbers triangle arrives at a Root Number of 5 as well - it is the same digit sum, reduced in stages - and what that book adds is the intermediate rows. The Kua formula gives 2 for a man and 4 for a woman born that year. Mulank, Bhagyank and Life Path and missing numbers in the Lo Shu grid go further into the first two, and the numerology tool runs the core profile on one page.

Life areas: two composites

Career and Money is a composite. It needs the Ascendant because it reads the 10th house and its lord, the Dashamsa, the Atma and Amatya Karakas, the running Mahadasha and today's transits together, with the Mulank and Bhagyank beside them. For the sample it opens with the 10th house in Cancer, its lord the Moon exalted in the 8th, and Ketu in the 10th itself. Health Tendencies is deliberately narrower than its name. It reads only the missing digits of the Lo Shu grid and reports the body areas Numerology Masters Notes (pp. 166-175) associates with each - not the specific illnesses that source lists - and it says in its own output that it knows nothing about your health. It is a classical association with a date of birth, and it is not medical advice.

One birth, climbed rung by rung

With the date alone

Type only 11 December 1989 and the chart is cast for 12:00 IST, with the timezone flagged as assumed. Moon Sign answers Taurus, 5.81 degrees, Krittika pada 3 - and prints the day's range beside it: Aries and Krittika pada 1 at 00:00, Taurus and Rohini pada 1 at 23:59. Checked minute by minute, the Moon entered Taurus at 02:42 IST and Rohini at 18:44. Sun Sign answers Scorpio, in Jyeshtha, with no change during the day. Moon Phase gives the 14th tithi of the bright half, the 13th at midnight. Vimshottari, cast from the noon Moon, shows a Sun period to October 1991 and a Rahu Mahadasha from 30 October 2008 to the night of 30 October 2026, with Jupiter to follow. Sade Sati shows the consequence of the Moon's sign change directly: at the start of the day the Moon is in Aries and Saturn in Pisces is the 12th from it, the rising phase; at the end of the day the Moon is in Taurus and nothing is running.

Adding the time

Add 05:10 and the range disappears, because there is now a moment to read. The Moon is at 1.54 degrees of Taurus, Krittika pada 2 - the same sign as the noon answer but an earlier pada, with nearly seven hours less of the nakshatra crossed. That moves the whole dasha calendar: the Rahu Mahadasha now runs from 1 October 2010 to 30 September 2028. A reader relying on the date alone on 5 October 2026 would have been told that Jupiter's period was under four weeks away; with the time, it is almost two years away. The three time-only calculators open as well: the sub-lord table, the Kaal Sarp test and the 12th from the Karakamsa. No house appears anywhere yet, and the server will not compute one from a time without coordinates.

Adding the place

Add Jaipur and the Ascendant exists: Libra, 29.34 degrees, in Vishakha. The houses follow by whole signs, so Scorpio is the 2nd and holds the Sun and Mars, and Taurus is the 8th and holds the Moon. Every calculator on the page now runs. It is also the most fragile reading on the page. The Ascendant is 0.66 of a degree from the end of Libra. Run the same birth at 05:14 and it is Scorpio 0.20: every house number above shifts by one, the Navamsa Lagna moves from Gemini to Cancer, and the Shashtiamsa Lagna, which was Leo at 05:10, has already passed through Virgo. The translator's note to BPHS Ch. 3 gives the scale: a sign takes roughly two hours to rise, so each degree takes about four minutes, varying with latitude.

What a few minutes of birth time move

The sample is not unusual. To put numbers on it, 20,000 birth moments were drawn at random between 1950 and 2010 for eight Indian cities, and each chart was computed twice by this engine: at the drawn moment and again a little later. The table shows how often each answer changed.

Three things follow. The Lagna-based readings stand or fall together: when the rising sign changes, the houses, the yogas, the Ashtakavarga totals and the Chara Dasha sequence change with it. The finer the division, the less a rounded birth time can support it: the Shashtiamsa Lagna was different four minutes later in every one of the 20,000 charts, which is the practical meaning of a half-degree division. And the Moon-based readings are sturdy by comparison, except in one respect - dates. A birth time one minute out moves the end of the first Mahadasha, and every boundary after it, by a median of 3.8 days; four minutes moves them by about 15 days, fifteen minutes by about two months, and an hour by a median of 234 days. The Accuracy feature is where the signed-in app keeps track of how much of a reading rests on the birth time.

How to read each kind of answer

• Unavailable, with a reason. The calculator needs a rung you did not supply. It names which - birth time, birth place, a name, a name in Latin letters - and computes nothing. That is a complete answer, not a fault.
• A reading with a day range. You gave a date without a time. The main figure is for local noon; the range shows the first and last minute of that date and whether they differ. If they differ, treat the main figure as one of two or more possibilities.
• A note that the timezone was assumed. No place or zone reached the server, so the clock was read as IST. For a birth elsewhere the instant is off by the difference between the two clocks, and the Moon moves about half a degree an hour. Give the place.
• A dated period. Dashas, the Personal Year, Varshaphal and the Sade Sati phase come as dates or named phases. The dates are only as exact as the birth time behind them, as the table above shows.
• A band or a score. Strong, Medium or Weak; a Vimshopaka total out of 20; a muhurat score out of 100; an Ashtakoot total out of 36. Each comes with the components that produced it, and the cut-off points are the engine's own unless the page cites a text for them. Compare bands within one chart, not across apps.
• A list of findings. Yogas, doshas and grid combinations are listed with the grahas or digits that form them. An empty list means none of the rules that calculator tests matched; it does not mean the chart is blank.
• A field deliberately left empty. The Kaal Sarp type, the Ishta Devata, the lord of the Varshaphal year. In each case the page gives the reason: no text in the library supports filling it in, or the engine lacks a table the classical method requires.
• A statement of the frame. The panchang family prints whether the day was cut from true sunrise at a named place or from the fixed clock; the personal-cycle pages print which calendar date, on whose clock, counted as today.

When two calculators disagree

The closing panel above says these systems often disagree and that the app shows it. The sample shows what that looks like in practice.

• Three calendars, three answers. Vimshottari, from the Moon's nakshatra, has the sample in a Rahu Mahadasha until September 2028. The numerology dasha, from the Mulank, began a nine-year Mars period on 11 December 2024. Chara Dasha has Taurus running until December 2033. They are built on three different premises, and none is a correction of another.
• Two Personal Years. The Personal Year page returns both. The day-month-year formula gives 6 for the whole of 2026 and 7 from 1 January 2027. The Vedic formula, which adds the weekday of the birthday and runs birthday to birthday, also gives 6 - until 11 December 2026, when it becomes 1. For three weeks the two disagree by design. The Personal Year article covers the first formula.
• Two letter tables. The name Aarav Kapoor has a Soul Urge of 7 on the Pythagorean table the Numerology Profile uses and 9 on the Chaldean table the Name Number calculator uses. Same vowels, different values.
• Two nodes. The Kaal Sarp page tests its verdict on the mean node and again on the true node, 1.13 degrees away for the sample, and reports whether they agree. Here they do.

A disagreement of this kind is information about the methods, and the honest display is side by side. The convergence page runs astrology and numerology on one birth date and shows whether they agree about the next twelve months, and when astrology and numerology disagree about your year works through one case.

What this set does not do

• It is not a full ephemeris. The planetary elements are valid from 1800 to 2050, and a point within a few arcminutes of a boundary can fall on the other side in one.
• There are no switches. One ayanamsa (Lahiri), one node (mean), one house system (whole sign). A chart drawn elsewhere on other choices will differ, and neither is thereby wrong.
• Shad Bala is the 20-point condensed version described above, not the Virupa computation of BPHS Ch. 27.
• Some classical outputs are withheld on purpose: three of the special dashas, the lord of the Varshaphal year, Kaal Sarp type names, a deity from the Karakamsa.
• Varshaphal is cast for the birth place. Classical practice is divided between the birth place and the place of residence, and only the birth place is known to the page.
• There is no gemstone, rudraksha or remedy calculator. That is a decision, set out in the questions below.
• Nothing here is medical, legal or financial advice, and no calculator issues a guarantee about an outcome.

Where to go from here

• For the whole chart read together: the Kundali feature, which the single-purpose pages above are closer looks at.
• For numbers as a system: the Numerology feature; for two people, the Compatibility feature.
• For choosing a moment or asking about one: the Muhurat feature and the Prashna feature; for today, the Daily feature.
• For work and money across the chart: the Career and Money feature.
• For three calculators on full pages of their own: the free tools. For the reading behind the methods: the articles.

Questions people ask about the calculators

Which calculators can I use if I do not know my birth time?

Everything on the first four rungs of the ladder: the five day calculators, the twenty-two birth-date entries (Moon Sign, Nakshatra, Vimshottari Dasha, Sade Sati, matching and all the date-based numerology among them) and the name and Kua calculators. The sky-reading ones show the range for your birth date. On about 96% of dates the Moon's nakshatra is not the same at both ends of the day, so read the range and not just the noon figure. The article on unknown birth times sets out the cost in full.

Why does a calculator say it is unavailable instead of estimating?

Because the estimate would look exactly like a real answer. Without a time and a place there is no Ascendant, and a house computed from a default coordinate is an invented number. The code records that an earlier version did exactly that - it cast an Ascendant at latitude 0 for a birth with a time and no place and printed a house from it - which is why the server now names what is missing and stops.

How precise does my birth time need to be?

It depends on the rung. The Moon-based readings survive an hour's error in most charts, but their dates do not: an hour moves each dasha boundary by a median of 234 days. The Lagna is unchanged four minutes later in about 96.7% of charts and fifteen minutes later in about 88%. The Navamsa Lagna changes within four minutes in 30% of charts, and the Shashtiamsa Lagna in all of them. If your time is rounded to the quarter hour, read the Rashi chart with some confidence, the Navamsa as provisional and the finest vargas as demonstrations of the method.

Why do my results differ from another app or a printed kundli?

Usually for one of five reasons, all of them checkable. The ayanamsa: this engine uses Lahiri, and another ayanamsa moves every longitude by the difference. The node: Rahu here is the mean node, up to about 1.9 degrees from the true node. The houses: whole-sign, so a chart drawn on another house system can place a graha one house away. The clock: a birth outside India read on IST, or a summer birth read without daylight time, is off by the difference. And precision: the Moon here is good to about 0.1 to 0.3 of a degree, so a point very close to a boundary can fall on the other side elsewhere. Why two apps give you two different nakshatras works through the commonest case.

Are these the same calculations the signed-in app uses?

Yes - the same functions. Each calculator page validates the input, calls an engine function that already serves the signed-in app, and returns what came back; the dispatcher's own file contains no arithmetic. One example of the care taken to keep the two identical: the Vimshottari calculator reuses the timeline the chart engine built from the unrounded Moon, because recomputing it from the rounded longitude moved every dasha boundary by minutes and made the calculator disagree with the signed-in chart about the same person.

What happens to the details I type?

The note above says nothing is saved; the mechanism is that the public calculator routes write nothing to the database - no record and no counter. The shared calculator endpoint echoes back only your date, whether a time and place were usable, the place label and the timezone, not the coordinates. The one outside call a calculation can make is a place-name lookup to resolve coordinates: a bundled list of cities first, then the Open-Meteo geocoder. Requests are limited to twenty a minute per connection.

Can I use these for a birth outside India?

Yes, if you give the place. A resolved place supplies its named timezone, and the offset is taken for the actual birth date, so daylight time is applied where it was in force - a July birth in London is read one hour ahead of Greenwich, not at zero. Without a place the clock is assumed to be IST and the result is flagged. The sunrise-based day calculators work for any place where the Sun rises and sets on that date.

Why is there no gemstone, rudraksha or remedy calculator?

By decision. The catalogue's own notes record that the gemstone and rudraksha recommenders are deliberately absent, and the app's guidance is limited to behavioural suggestions - no gemstone, ritual, chanting or donation. Where a classical source prescribes a remedy or predicts a frightening outcome, the engines carry the structural fact - which sign, which house, which period - and leave the prescription out.

Which calculator should I start with?

The one that matches what you know. With a date only: Moon Sign, Nakshatra and Vimshottari Dasha, read with their day ranges, and Life Path. With a date, time and place: the Birth Chart first, since every other Ascendant-level page is a closer look at part of it, then the Navamsa and Shad Bala. For today and not for you: the Panchang.