The tithi is the most important limb of the Panchang. Most Hindu festivals and fasts — Ekadashi, Janmashtami, Diwali — are fixed by tithi rather than by the solar calendar date.

How a tithi is measured

A tithi is defined by the elongation of the Moon: how far the Moon is ahead of the Sun in longitude. Every time this angle grows by 12°, a new tithi begins. Since a full cycle is 360°, there are 360 ÷ 12 = 30 tithis in a lunar month.

  • Shukla Paksha (bright fortnight): tithis 1–15, from Pratipada to Purnima (full moon), as the Moon waxes.
  • Krishna Paksha (dark fortnight): Pratipada to Chaturdashi, ending with Amavasya (new moon), as the Moon wanes.

The fifteen names are Pratipada, Dwitiya, Tritiya, Chaturthi, Panchami, Shashthi, Saptami, Ashtami, Navami, Dashami, Ekadashi, Dwadashi, Trayodashi, Chaturdashi and Purnima (or Amavasya).

Tithis do not match civil days

Because the Moon's speed varies along its orbit, a tithi can last from roughly 19 to 26 hours. It can begin at any time of day or night. Two consequences follow:

  • Udaya tithi — the tithi prevailing at local sunrise is generally treated as the tithi of the whole day for everyday purposes.
  • Kshaya tithi — a short tithi that begins after one sunrise and ends before the next is never "at sunrise", so it is said to be skipped (kshaya).
  • Vriddhi tithi — a long tithi that spans two sunrises appears on two consecutive days.

For festivals, however, many rules look at a specific time window — for example midday, pradosh (evening) or midnight — rather than only sunrise. That is why a festival sometimes falls on the day before the tithi appears at sunrise.

Tithi groups

Tradition groups the tithis of each paksha into five classes, repeating three times:

  • Nanda — 1, 6, 11
  • Bhadra — 2, 7, 12
  • Jaya — 3, 8, 13
  • Rikta — 4, 9, 14
  • Purna — 5, 10, 15 (Purnima/Amavasya)

Rikta ("empty") tithis — Chaturthi, Navami and Chaturdashi — along with Amavasya are traditionally avoided when choosing a muhurat for new beginnings, and this site's muhurat finder applies that rule. Traditions may vary by region and Panchang convention.

How this platform calculates it

We compute the exact start and end of every tithi from the Sun's and Moon's positions for your location, and list every tithi that touches the sunrise-to-sunrise day. See today's tithi on the Panchang page.