Vedic astrology calculator
Panchang Calculator
The Panchang is the Indian almanac of the day, built from five parts: the weekday, the tithi, the nakshatra, the yoga and the karana. Choose a date and a place to see which ones run from sunrise, when each one changes during the day, and how we calculated them.
What is the Panchang?
Panchang means five limbs. A day in the Indian calendar is described by five things: the vara (weekday), the tithi (the lunar day), the nakshatra (the lunar mansion the Moon is in), the yoga and the karana. The Indian day does not begin at midnight but at sunrise, and it runs until the next sunrise at the same place.
That is why a Panchang depends on the place: sunrise comes at a different moment in Delhi and in New York, and the element that is running at that moment gives the day its name.
The five parts
- Vara: the weekday of the local date, from Ravivara (Sunday) to Shanivara (Saturday).
- Tithi: the Moon gains 12° on the Sun. There are 30 tithis in a lunar month, 15 in the waxing half (shukla paksha) and 15 in the waning half (krishna paksha); the 15th is the full Moon (Purnima) and the 30th the new Moon (Amavasya). The tithi that runs at sunrise gives the day its number.
- Nakshatra: the sidereal longitude of the Moon divided into 27 parts of 13°20′, as in the nakshatra calculator.
- Yoga: the sum of the sidereal longitudes of the Sun and the Moon divided into 27 parts of 13°20′.
- Karana: half a tithi, so 6° of the Moon's gain on the Sun. There are 60 in a lunar month, with 11 names: seven that repeat (Bava, Balava, Kaulava, Taitila, Gara, Vanija, Vishti) and four fixed ones (Shakuni, Chatushpada, Naga, Kimstughna).
Sunrise, and why there are two
Almanacs do not all define sunrise the same way. We offer two: the visible sunrise, when the upper edge of the Sun touches the horizon with the usual refraction of 34′, and the geometric sunrise, when the centre of the Sun crosses the horizon. The geometric one comes about 4 minutes later, and it is the one Prokerala turned out to use when we measured it. We do not know which one the Rashtriya Panchang uses, because we have not been able to read it. Visible sunrise is our default.
It only changes the result when a tithi, nakshatra, yoga or karana ends within a few minutes of sunrise. When that happens we show the other one, as in the nakshatra calculator. We calculate at sea level; the height of the place is not used.
Our choices
- Positions as seen from the centre of the Earth (geocentric), not from your place (topocentric). For the Moon the two differ by up to about 1°, which moves a change by up to about two hours. We tested this: for Ujjain, geocentric nakshatra times agree with Prokerala within 1.1 minutes, while topocentric ones would be off by 53 minutes on average and up to 95.
- Ayanamsa: Lahiri (Chitrapaksha), the official standard in India, with the other systems as a choice.
- Day: the Panchang of the local date starts at sunrise on that date, even if you look after midnight.
- Times in the local time zone of the place; for dates before 1906 that means, in India, the historical zone (Madras time, UTC+5:21).
How we calculate, and what we checked
Positions of the Sun and Moon come from the Astronomy Engine library. The tithi follows the Moon's elongation from the Sun, the nakshatra the sidereal Moon, the yoga the sum of the two sidereal longitudes, the karana half a tithi. The moments of change are found by searching for the moment each angle crosses its boundary. Everything runs in your browser, for dates from 1900 to 2100.
We compared the weekday, the names and the start and end of every tithi, nakshatra, yoga and karana (178 times) on 10 days between 1910 and 2030 with the daily Panchang of Prokerala for Ujjain. All names agree and the largest difference was 1.6 minutes. That is a calculation and not an official almanac, and we only checked this one place. We have not compared the results with the Rashtriya Panchang or the Indian Astronomical Ephemeris, we have no published source for dates after 2030, and we did not check places outside India.
What this calculator does not do
It gives the five parts, not auspicious moments, festival dates or predictions. Those depend on rules that differ between regions and traditions, and we do not present them as fact.
Sources and further reading
- William Sewell and Sankara Balkrishna Dikshit, The Indian Calendar (1896; public domain).
- Kim Plofker, Mathematics in India (Princeton University Press, 2009).
- Prokerala, daily Panchang (Lahiri ayanamsa, India local time), used to compare the results.
- Astronomy Engine (positions of the Sun and Moon) and the moon phases of the U.S. Naval Observatory (test of the Moon's position).