Tithi Calculator

A tithi is a lunar day in the Hindu calendar — the time it takes the Moon to gain 12° of elongation from the Sun. There are 30 tithis in a lunar month: 15 in the waxing fortnight (Shukla Paksha, ending in Purnima/full moon) and 15 in the waning fortnight (Krishna Paksha, ending in Amavasya/new moon). A tithi can be shorter or longer than a solar day, so its start and end times shift each day.

The tithi is the elongation between the Moon and the Sun divided into 12° steps. This calculator computes both the Moon’s and the Sun’s sidereal (Lahiri ayanamsa) longitudes with an astronomical engine verified against Swiss Ephemeris, then finds which 12° step you are in and the exact time it ends — the same method used by mainstream panchang.

Shukla Paksha is the bright, waxing fortnight from the new moon to the full moon (the Moon grows each night). Krishna Paksha is the dark, waning fortnight from the full moon to the next new moon. The same tithi names (Pratipada to Chaturdashi) repeat in both; the 15th of Shukla is Purnima and the 15th of Krishna is Amavasya.

Enter any date above and this calculator scans forward to find the next Ekadashi (11th tithi, observed with fasting), the next Purnima (full moon) and the next Amavasya (new moon), with their dates. Ekadashi falls twice a lunar month, once in each paksha.

A printed panchang usually labels a date by the tithi prevailing at sunrise. This tool gives the tithi at the exact time you enter, so if a tithi changes during the day you may see the next one. Use sunrise (around 6 AM) to match the conventional daily label, or your exact time for the precise current tithi.

Yes — after calculating, tap the Listen button to hear the tithi, paksha, when it ends and the upcoming Ekadashi, Purnima and Amavasya read aloud in Hindi or English. Free audio in your browser.