The sunrise-based Hindu day

A day from sunrise to sunrise

In the Gregorian calendar a day runs from midnight to midnight. In the Hindu Panchang the day runs from one sunrise to the next.

The reasons are practical and old. Before clocks, sunrise was the clearest marker, visible to anyone. Rituals, fasts and daily prayer are tied to dawn.

What changes at sunrise

At sunrise in your city, several things change together.

• The weekday (vara). Monday begins at Monday's sunrise and lasts until Tuesday's sunrise. If it is 3 a.m. and the date has changed on your phone, the Hindu weekday is still the one before.
• The tithi of the day. The tithi running at sunrise names the day, as explained on the page on the udaya tithi rule.
• Daily timings. Rahu Kalam, Choghadiya and Abhijit Muhurat are all found from sunrise and sunset.

The other limbs, nakshatra, yoga and karana, change at their own times and are not tied to sunrise. The site always shows the exact times.

The night belongs to the day before

Because the day begins at sunrise, the hours after midnight and before dawn belong to the previous Hindu day. If a festival is on a certain day, the night before sunrise on the next civil date is still part of that day. Overnight observances, such as Maha Shivaratri vigil or Navratri night prayers, continue past midnight within the same Hindu day.

Brahma Muhurta, the quiet time before dawn, is also counted as part of the previous day by the Panchang.

What counts as sunrise

Sunrise is calculated for the exact place. The usual convention is the moment the upper edge of the Sun appears at the horizon, allowing for the bending of light in the air. Different panchangs may differ by a minute or so, depending on whether they use the upper edge or the centre and how they treat refraction. This site computes it astronomically for your chosen city.

Sunrise differs a lot by place and season. In the USA, it can be before 5:30 a.m. in a northern city in summer and after 7:00 a.m. in winter. Daylight saving time moves the clock reading by an hour twice a year.

Why this matters

• A tithi that the Panchang gives for "a date" is the tithi at that date's sunrise, in your city.
• A tithi that begins after sunrise on one date and ends before sunrise on the next does not name any day. That is the kshaya tithi.
• Festivals with an evening or midnight observance follow the tithi at that hour, not the one at sunrise.
• Two cities in different parts of the USA may sometimes have different Hindu days for the same civil date, if the tithi changes between their two sunrises.

Sunrise to sunrise in other places

Some regional calendars may apply different conventions for certain purposes. This site follows the sunrise-to-sunrise rule common to most Panchangs. If your community follows another rule, your priest will tell you.

Simple summary

Think of the Hindu day as starting with the Sun. Before dawn you are still in yesterday. At sunrise the day, its weekday and its tithi begin. All times on the site are shown in your local time zone, so you can read them directly from your clock.