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How accurate is this almanac?

Every time on this site is computed, not copied from a table. Here is what it is computed from, what it was checked against, and — just as importantly — what it does not do.

Panchang or Panchangam?

The same thing. Panchang is the Hindi and North Indian way of saying it; Panchangam is the Sanskrit form, and the one used across South India. Bengal says Panjika, Odisha Panji, Nepal Patro. The word means “five limbs” — tithi, vara, nakshatra, yoga and karana — the five readings every Hindu almanac gives for a day. Whichever word you searched for, this is it.

What the positions come from

A planetary ephemerisPositions come from a modern numerical planetary ephemeris — the class of data used for spacecraft navigation. Not a table, not an approximation formula — the ephemeris itself.
Lahiri ayanamsaThe Chitra Paksha ayanamsa, with nutation applied. This is the Indian government's official value, and the one every published Indian panchang uses, so a tithi here is the tithi your family's calendar names.
Your own horizonSun and Moon are computed topocentrically — from where you stand on the surface, not from the centre of the Earth. The Moon's parallax is about a degree, which is two Moon-widths, and it is the whole reason an eclipse is total in one town and partial in the next.
Computed from the skyTrue computed positions rather than the mean positions of the old astronomical texts. Tradition calls this observational reckoning, and it is an approach rather than a rival source of data: the ephemeris supplies the positions, and the reckoning is what is done with them.

The science behind the calculation

All five limbs of the panchangam come from two numbers: where the Sun is, and where the Moon is. Everything else is arithmetic on those two angles — which is why a single error in one of them shows up in several places at once, and why the fields that depend on the Moon alone agree most closely with other engines.

TithiMoon − Sun, divided by 12°A lunar day is how far the Moon has pulled ahead of the Sun. Thirty steps of twelve degrees make one lunation, so the tithi number is that gap divided by twelve. Because the Moon's speed varies, a tithi runs anywhere from about 21½ to 26 hours — which is why it does not line up with a calendar day and why the app gives you the exact moment it ends.
NakshatraMoon, divided by 13°20′The Moon's own position against the fixed stars, in 27 equal parts. It depends on one body rather than two, which is why it is the field that agrees most closely with other engines — two seconds, here.
YogaMoon + Sun, divided by 13°20′The sum of the two longitudes, in the same 27 parts. Not a conjunction of anything visible; an arithmetic combination with its own named cycle.
KaranaHalf a tithiSixty per lunation, so two per tithi. Both the current one and the next are shown, because a karana changes mid-day far more often than a tithi does.
VaraSunrise to sunriseThe weekday changes at sunrise, not at midnight — so does Rahu Kaal, choghadiya and hora, all of which divide the day from sunrise to sunset and the night from sunset to the next sunrise. Get sunrise wrong and every one of them moves.

The corrections that do the work

Raw positions are not enough. Five corrections separate a number that looks right from one that survives comparison with a published almanac.

Sidereal, not tropicalWestern positions are measured from the moving equinox; a panchangam is measured against the fixed stars. The difference is the ayanamsa — currently about 24°, a whole sign either side of wrong if you skip it. We apply Lahiri (Chitra Paksha), with nutation.
Topocentric, not geocentricThe Moon is close enough that where you stand on the Earth changes where it appears by up to about a degree — two Moon-widths, or roughly four minutes of tithi. Positions are computed from your own point on the surface.
Apparent, not geometricLight takes time to arrive and the Earth moves while it does. Aberration and light-time are applied, so the positions are where the bodies appear now rather than where they were.
Delta-TThe Earth's rotation is not a perfect clock, so dynamical time and universal time drift apart — about 69 seconds today. It is applied before any comparison with a published table, which is the step that makes a correct eclipse time look correct.
Solved, not steppedTransition moments — when a tithi ends, when the Sun crosses the horizon — are found by root-finding on the underlying function, not by sampling every minute and taking the nearest. That is the difference between a time good to the second and one good to the minute.

Checked against a reference almanac

The reference is a widely used online almanac that computes from a planetary ephemeris rather than from printed tables. Compared field by field, to the second, in three seasons — midsummer, the equinox and midwinter:

Nakshatra end0–3sThe Moon’s own position, effectively identical.
Varjyam and Amritkalam0–3sBoth are cut from the nakshatra, so they inherit its agreement.
Abhijit Muhurta1–3sCentred on true solar noon.
Tithi and karana endup to 9sMeasured on the apparent Sun and Moon — see below.
Yoga endup to 11s
Sunrise / sunset11–17sOne understood cause — see below.
Moonriseup to 19s

Two earlier differences were tracked to their causes and closed. Tithi and karana once ran 49 seconds late: they are now measured on the APPARENT Sun and Moon, as an almanac defines them, and agree to within nine seconds. Sunrise and sunset once differed by a minute: sunrise is now the moment the centre of the Sun’s disc reaches the horizon with refraction for your own altitude, and the remaining 11 to 17 seconds is a small difference in the refraction constant assumed. It is the same at sunrise and sunset in every season, which is what a single cause looks like, and an independent astronomical service puts the Sun within a thousandth of a degree of the horizon at our instants.

Checked against the eclipse canon

Greatest-eclipse times against the standard published canon of solar eclipses for 2001–2100. The canon quotes Terrestrial Dynamical Time; the engine's own delta-T is applied before comparing.

2017 Aug 21+1sThe American total eclipse.
2024 Apr 08+5s
2026 Aug 12−4s
2027 Aug 02+1sThe long one over North Africa.

Checked against what people saw

Agreeing with another calculation is not the same as agreeing with the sky. These are computed local circumstances against what was actually observed and published.

Hopkinsville, KY — 2017100%On the path. Computed magnitude 1.004; totality was observed.
New York — 201759%Off the path. Computed magnitude 0.668; a deep partial was observed.
New York — 202489.9%Computed maximum at 3:26 PM. Published figures: about 89.6% at about 3:25 PM.

Checked across thirty years

Festival rules are easy to fit to the year you are looking at. These were re-run against years they were never tuned on — 13 of 13 correct for 2026, 8 of 8 for 2027, and 8 of 8 across 2000, 2010, 2020 and 2030.

Your own calendar, laid over it

Choose a calendar tradition in your profile and the almanac is read the way your family’s is: thirty traditions, covering every Indian state with its own reckoning and Nepal, Sri Lanka, Bangladesh and Bhutan. Nothing computed changes. What is added is the region’s own months, its year and the name of that year, its festivals, and its words.

When a month beginsEach region has its own rule for the day a solar month starts when the Sun changes sign part-way through a day: before sunset in Tamil Nadu, before mid-afternoon in Kerala, the following day in Bengal and Assam, the day of the change in Odisha and Punjab. Nepal’s months follow the table its national committee publishes. Every rule was checked against a run of published month-starts, not a single date.
Which Sun a region followsBengal, Assam and Nepal date their months from the traditional Sun of the old astronomical texts, which now runs some hours behind the true one; the others follow the true Sun. The app uses whichever each region’s own almanacs use, and marks a month whose start falls within an hour of the day’s turn, where a printed almanac may differ by a day. The traditional Sun only ever names months — no time on this site comes from it.
Festivals, for where you areA lunar day or a star is one moment for the whole world, but each place meets it at a different hour of its own day. So Deepavali in 2026 is 8 November in Chennai and 7 November in Atlanta, and both are right. Every festival is worked out for the place you set, by the rule that festival is actually decided on — sunrise, midday, dusk, moonrise or midnight.
The year and the seasonThe year is numbered and named as your tradition does it — the southern and northern sixty-year cycles are thirteen names apart, and Gujarat’s year turns at Diwali. Almanacs also print two seasons, the Vedic one and the one the weather keeps, which are a season apart for much of the year; both are shown.

In your own words

The calculation never deals in words. It produces bare facts — the twenty-second lunar day, the eighteenth star — and only then are they said, in the vocabulary of the tradition you chose: fifteen of them, from Tamil and Malayalam to Punjabi, Bengali, Odia, Assamese, Nepali and Kashmiri. Because the two are kept apart, a change of words cannot change a value. Names follow how each community writes them in English, not a transliteration rule, and where a reliable list could not be found the Sanskrit name is shown rather than an invented one.

The order changes too. A Tamil or Malayali almanac reads the day by its star, so the star leads; the South checks Rahu Kalam, Yamagandam and Kuligai first, the Telugu country Varjyam and Durmuhurtham, the North Abhijit. Tamil Nadu also gets its own table of good and bad hours, the Gowri Panchangam — the Nalla Neram — in place of the Choghadiya read in the North and West. Neither is South Indian as such: Telugu and Kannada almanacs print no Gowri table and check Varjyam, Durmuhurtham and Gulika instead.

Your birth chart

Birth chart, birth star and name syllable, Mangal and Kalasarpa, Sade Sati, horoscope matching by both the northern thirty-six points and the southern ten, gemstone and rudraksha, the Pancha Pakshi bird, Vedic time, the yearly shraddha of a loved one, the star birthday of everyone in your family, and lunar anniversaries. They use the same astronomy as everything else here, and were checked against published reference charts for three fixed test births: 36 of 36 readings agree. Where schools genuinely differ — how Mangal dosha is counted, which day a thousandth full moon is kept — the page shows the difference instead of choosing silently. Everything they are computed from stays on your device, encrypted.

What it does not do

Lagna shuddhiWhether the rising sign at your chosen hour is afflicted. Astrologers call this the deciding test for a muhurta, and it needs a chart cast for the exact moment. The rising sign is shown; it is not judged.
Birth chart doshasNeither person's chart is read for Mangal dosha or anything like it.
Every regional tableThirty calendar traditions are covered, but not every table in every one. The eastern panjika’s Amrita and Mahendra yoga and its Barbela and Kalbela are not here yet, and a few festivals are left out because published almanacs disagree on their date. Wedding star lists also differ by family; each page names the list it used.
Holi, in some yearsHolika Dahan can land a day out. Pradosh is the right principle but not the complete rule, and the obvious fix — skipping days whose pradosh falls in Bhadra — was tried and is wrong.

Your data

The almanac runs on your device, so most of what you do here never reaches us at all. Birth details — yours, your family’s, and those of loved ones remembered for a shraddha — stay on the device, encrypted with AES-256 under a key that never leaves it, and deleting the app deletes them. So do your gender and your gothram. Your account holds three things \u2014 your email address, your name, and whether you have paid \u2014 and nothing else about you. There is no analytics SDK, no advertising SDK and no tracker anywhere in the app. Signing in uses an emailed code rather than a password, so there is no password to lose. The privacy page lists every field that leaves the device, where it goes, and what is not claimed.

Questions people ask

Is a Panchang the same as a Panchangam?

Yes — they are one word. “Panchang” is how it is said in Hindi and most North Indian languages; “Panchangam” is the Sanskrit form, and the one used in Tamil, Telugu, Kannada and Malayalam. Both mean “five limbs”: the five things the almanac gives for every day — tithi (lunar day), vara (weekday), nakshatra (the Moon's star), yoga and karana. Bengal calls the same book a Panjika, Odisha a Panji, Nepal a Patro. This site uses the two words interchangeably.

Why is a festival on a different date in the USA than in India?

A tithi or a nakshatra is one moment in the sky for the whole world, but each place meets it at a different hour of its own day. A festival belongs to the local day on which its tithi holds at the deciding moment — usually sunrise, sometimes midday, dusk, moonrise or midnight. So Deepavali in 2026 is 8 November in Chennai and 7 November in Atlanta or Louisville, and Ugadi is 19 March in India but 20 March in Sydney. This panchang works every date out for your own city, which is why it can differ by a day from a list printed for India.

Does it follow my state's calendar — Tamil, Telugu, Bengali, Gujarati, Punjabi, Nepali?

You can choose a calendar tradition in your profile: every Indian state with its own reckoning, plus Nepal, Sri Lanka, Bangladesh and Bhutan — thirty in all. The almanac is then read in that tradition's own words, too: the lunar days, stars, weekdays and the day's windows are named as your family's almanac names them, and listed in the order it reads them. The panchangam itself never changes; the regional months, year and festivals are laid over it — Tamil and Malayalam solar months, Telugu and Kannada lunar months ending at the new moon, North Indian months ending at the full moon, the Bengali, Assamese and Odia solar months, Punjab's Sangrand, and Nepal's Bikram Sambat. Each region's month-start rule is its own, and each was checked against published dates.

Why do Tamil and Gujarati readers see different names for the same thing?

Because they are the same thing. The calculation produces one fact — the seventh lunar day of the bright half, the eighteenth star — and the app then says it in the words of the tradition you chose: Valarpirai Sapthami and Kettai in Tamil, Sud Satam and Jyeshtha in Gujarati. Fifteen vocabularies are covered. Changing the tradition changes every name and the order things are listed in; it never changes a time.

What is the Choghadiya, and how is it different from Rahu Kaal?

The Choghadiya is the day and the night each cut into eight named parts — Amrit, Shubh and Labh good, Char neutral, Rog, Kaal and Udveg set aside — with the weekday fixing the order. It is the everyday check of North and West India. Rahu Kaal is a separate reckoning: one eighth of daylight, chosen by the weekday alone. They are counted differently, so a good Choghadiya can fall inside Rahu Kaal; the app shows the overlap rather than hiding it, and most people then pick another good part.

What is Gowri Panchangam, and is it the same as Nalla Neram?

Gowri Panchangam is the Tamil reckoning of the good hours and the ones to avoid: daylight and the night are each cut into eight equal parts, five of them good (Amirdha, Uthi, Laabam, Sugam, Dhanam) and three set aside (Rogam, Soram, Visham), with the weekday deciding which falls where. Here the parts are measured from your own sunrise and sunset, not from a fixed six o'clock. It is not the same as the Nalla Neram row on a printed daily sheet, which is a separate, nearly fixed table chosen by its publisher.

Is the birth chart (kundali) accurate?

They use the same astronomy as the rest of the almanac, with the conventions mainstream Indian practice uses: whole-sign houses, the Moon's mean node for Rahu and Ketu, and the Vimshottari dasha in years of 365.25 days. Checked against published reference charts for three fixed test births, 36 of 36 readings agree — every sign and star, the house of all nine grahas, the Mangal and Kalasarpa verdicts, the dasha lord, and every one of the eight kootas in a horoscope match. A birth chart is cast on your device; the details are never sent anywhere.

What data is this panchangam calculated from?

A modern numerical planetary ephemeris, with the Lahiri (Chitra Paksha) ayanamsa and nutation applied. Sun and Moon positions are topocentric — computed for your own latitude, longitude and horizon rather than for the centre of the Earth.

How close is it to a reference almanac? Independently, at the app’s own sunrise and sunset instants a space agency’s planetary ephemeris service puts the Sun’s refracted centre within 0.0007° of the horizon — under a fifth of a second of time.

Compared field by field, to the second, in midsummer, at the equinox and in midwinter: the nakshatra, Varjyam, Amritkalam and Abhijit agree within three seconds; tithi and karana within nine; yoga within eleven; sunrise and sunset within eleven to seventeen; moonrise within nineteen. Each remaining difference has one understood cause rather than being scattered error.

Why can sunrise still differ by a few seconds from another almanac?

Sunrise here is the moment the centre of the Sun's disc reaches the horizon, with atmospheric refraction worked out for your own altitude. Almanacs assume slightly different refraction, and some take the Sun's upper edge instead of its centre, which alone moves sunrise by about a minute. Everything divided from sunrise and sunset — Rahu Kaal, Choghadiya, the planet hours, the Gowri parts — inherits that one difference. It is one cause, not nine separate ones.

Are the eclipse times reliable?

Greatest-eclipse times agree with the standard published canon of solar eclipses to within five seconds on every eclipse checked. The canon is published in Terrestrial Dynamical Time and this app works in UTC, so the engine's own delta-T is applied before comparing — skipping that step makes a correct result look 69 seconds wrong.

Which month system does it use?

Amanta, where the dark fortnight keeps the preceding month's name. A Purnimanta source calls Diwali “Kartika Krishna Amavasya” and this app calls it “Ashwina Krishna Amavasya” — the same day under another name. Leap months are marked Adhika and Nija, and festivals fall in the Nija month.

Have the festival dates been checked?

Yes. Every rule was checked against published dates before it was kept, and against years it was never tuned on: the general festivals match 30 of 30 across 2025 to 2027, the regional festivals 239 of 241, the Tamil solar festivals 29 of 29, Punjab's month-starts 24 of 24 and Nepal's 25 of 25. Where published sources contradict each other the festival is left out rather than guessed, and the page says so. Holika Dahan and Holi can still be a day out in some years; that limit is documented rather than hidden.

Does the app store my date and time of birth?

Only on your own device. Your birth details, your family's, and the details of loved ones you remember for a shraddha are kept on the device, encrypted, and are never sent to our server — including from the profile page. Your gender and your gothram are kept there too. What the account holds is your email address, your name and whether you have paid — nothing that describes you. Every calculation runs on your device, so nothing needs to be sent. “Forget” beside any person erases them, and deleting the app deletes everything it kept. The trade-off, stated plainly: the details do not follow you to a new phone.

Does the app track me or show ads?

No. There is no analytics SDK, no advertising SDK, no tracking pixel and no third-party cookie. Fonts are served from our own origin, and place lookups go through our own server, which passes on only the place name or a position rounded to about a kilometre — never your IP address — and keeps no record. Your browser only ever talks to us: the site instructs it to refuse every other server, so a tracker cannot be slipped in without the browser blocking it.

Is my data encrypted?

Yes. Birth details — yours, your family's, and loved ones remembered — are encrypted on your device with AES-256 before they are stored, using a key created on the device that cannot be read out of it. In the iPhone app they also sit inside the app's own storage, which iOS encrypts at rest and deletes with the app. In transit everything is over HTTPS, and there is no password to steal: signing in emails a six-digit code, and the code is never stored — what travels is a SHA-256 hash, compared in constant time. What we do not claim: the name and choices saved with your account are readable by the service that stores them, and encryption on the device protects the stored copy, not a phone that is already unlocked in someone's hand.

What is the Shraddha tithi, and why can it differ from today's tithi?

It is the tithi a shraddha — the yearly offering to an ancestor — is kept on, and it is decided at aparahna, the fourth of the five equal parts of daylight, because that is the hour the offering is made (Dharmasindhu; Nirnaya Sindhu). The sunrise tithi names the day, but whenever it ends before the afternoon the next tithi is the one running at aparahna. Worked out for Chennai across 2026, that happens on 135 days of 365. The home page shows it in your own tradition's words — Srardha Thithi on a Tamil sheet, Shraddh Tithi in Hindi — every day for Tamil Nadu, where daily sheets print it, and elsewhere on the days it differs, with the hour that decided it.

How do I find the shraddha date for a loved one each year?

Enter when and where they passed away. The tithi is the one running at that moment at that place — the place's own time zone is what turns the date and time into the moment. Each year's date is then found where the rite is kept, which is where you live now: the day on which that tithi is running at aparahna there, in the same lunar month (the extra month of a leap year keeps no rites). If the time is not known and the tithi changed that day, the page shows each part of the day with its tithi and asks which it was, rather than guessing. When a tithi never touches aparahna in a year, it is kept on the day it begins, as the texts direct. Details can be saved for several people, on your device only.

What is a star birthday, and how is it worked out?

In much of South India the birthday kept is the day your birth nakshatra returns in your birth month — Janma Nakshatram, or Pirannal in Kerala — rather than the Gregorian date. The month is the solar month you were born in, counted by your tradition's own solar calendar (Tamil, Malayalam, Punjab and Tulu each begin their months by their own rule); the day is the one in that month whose star at sunrise is your birth star, for the place you live now. A star can come twice in one solar month; families differ on which to keep, so both dates are shown.

Can I keep my family's details, and in my own language?

Yes. Add each family member's date, time and place of birth — or just their star, if the time is not known — and the home page lists everyone with their star, sign and next star birthday. Relations are named in your tradition's words: Appa and Amma in Tamil, Pitaji and Mataji in Hindi, Baba and Maa in Bengali, Nanna and Amma in Telugu, with grandparents split by side where your language splits them (Dadaji and Nanaji, Thakurda and Dadu). Change the tradition and everyone is renamed at once. All of it stays on your device, encrypted.

Which panchangam does this follow — Vakyam or Thirukanitham?

Thirukanitham: the computed method, positions from a planetary ephemeris, the method Indian almanacs call Drik Ganita. Vakyam, used by many Tamil almanacs for rituals, works the Moon out from a medieval table with a single correction of about five degrees and leaves out the Sun's pull on the Moon. Measured against seventeen years of printed Vakya almanacs, the two agree at new and full moon but drift up to about five hours apart near the quarter moons, so the tithi at sunrise differs on roughly one day in eleven and a solar month can begin a day apart. Neither is wrong for its purpose; this app shows the computed sky, and says so.

Do I need an account to use it?

No. Today's panchangam, the hours, the festival dates and the eclipses all work signed out and without a location permission. An account exists so a purchase can follow you to a new phone.

Is it a subscription?

No. One purchase of $9.99 unlocks every date, permanently — in store terms a non-consumable, not a subscription. Nothing renews and nothing expires. Today's panchangam is free for everyone, always.

Can it choose a wedding date on its own?

No, and it does not claim to. It checks the nakshatra, the lunar day, the weekday, whether Jupiter and Venus are visible, and — if you enter birth details — Tara Bala and Chandra Bala for each person. It does not check lagna shuddhi, which astrologers call the deciding test, and it does not read either birth chart for doshas. It produces a shortlist with the reason for every verdict, including the failures.

What the numbers rest on

A planetary ephemerisA modern numerical ephemeris — the class of planetary data used for spacecraft navigation. It is the basis of every position on this site.
The published eclipse canonThe standard catalogue of solar eclipses for 2001–2100. Every eclipse peak here was compared against it.
A reference almanacA widely used online panchangam computed from the same ephemeris, measured against field by field.

Want to see it working? Open the almanac — every page computes its times for the place you set, and says which place that is.