Karva Chauth Moonrise Calculator

This calculator tells you the one number that matters most on Karva Chauth — the exact moonrise time for your city, the moment the day-long fast can finally be broken. It also shows the festival date for the year you pick (already fixed by the Hindu lunar calendar), the sunrise that marks when the fast begins, and the total length of the fast in hours. It is built for the millions of married women across North and West India — and the families supporting them — who observe Karva Chauth each year and need a city-accurate time rather than a vague nationwide estimate copied from a newspaper.

What Karva Chauth is

Karva Chauth is observed on Kartik Krishna Chaturthi — the 4th day (Chaturthi tithi) of the waning fortnight (Krishna Paksha) in the Hindu lunar month of Kartik, usually falling in October or early November. Married women keep a nirjala (waterless) fast from sunrise, praying for the long life, health, and prosperity of their husbands. The fast is broken only after the moon is sighted: the woman views the moon and then her husband's face — traditionally through a chhalni (sieve) — offers arghya (a water libation) to the moon, and finally takes her first sip of water and bite of food from her husband's hand. The festival is most prominent in Punjab, Haryana, Rajasthan, Uttar Pradesh, Madhya Pradesh, and among North Indian communities everywhere, and is celebrated with the morning sargi (a pre-dawn meal from the mother-in-law), henna, festive dress, and an evening puja. Because the entire day's observance ends precisely at moonrise, getting that time right for your own location is what this tool is for.

Why moonrise time is so location-specific

Karva Chauth always falls about four days after Sharad Purnima (the autumn full moon), so the Moon is a waning gibbous that rises roughly 3-4 hours after sunset — typically between about 19:45 and 20:45 across most Indian cities. Moonrise is not a single national event. Because the Earth turns about 15° of longitude every hour, a city further east sees the Moon clear the horizon earlier than one further west. Kolkata (88.4° E) can see moonrise 25-30 minutes before Mumbai (72.9° E) on the very same date. Latitude matters too: depending on the Moon's declination that night, more northern or southern cities shift by a few extra minutes. This is why a wife in Mumbai may still be waiting when her sister in Delhi or Kolkata has already broken her fast — and why a city-specific time is essential.

How this calculator works

The festival date for each year is fixed by the Hindu lunar calendar and is pre-computed and verified against the Panchang for 2026-2030. For your selected city (or custom latitude/longitude), sunrise and sunset are computed with a standard NOAA-Almanac solar algorithm accurate to about ±2 minutes, and moonrise with a simplified Jean Meeus mean-elements lunar ephemeris that includes parallax and atmospheric-refraction correction at the horizon, accurate to about ±5 minutes. All times are shown in IST (+5:30). The fast duration is simply moonrise minus sunrise. The tool treats this respectfully as a cultural and devotional observance — it provides the astronomical timing, not religious instruction, and defers to your family's tradition on how the fast is actually broken.

Worked example

Suppose Priya in Delhi wants to plan Karva Chauth. She selects the year and the city "Delhi". The calculator fixes the festival date for that year, then computes sunrise for Delhi (around 6:25 AM in late October) — that is when her nirjala fast begins after the pre-dawn sargi. It then computes the Delhi moonrise (typically in the low 8 PM range) — the moment she can sight the moon, offer arghya, and break her fast. The fast duration shown is moonrise minus sunrise, roughly 13.5-14 hours. If her mother in Kolkata is observing the same day, Priya switches the city to Kolkata and sees moonrise appear about 25 minutes earlier, because Kolkata lies well to the east. The 5-city comparison table lets her see Delhi, Mumbai, Bengaluru, Kolkata, and Chennai side by side for the same date, so the whole family can coordinate.

Tips for using the result

Pick the city closest to you, or enter exact coordinates for a small town. Plan the evening puja and family gathering for 15-20 minutes before the computed moonrise so everyone is ready when the Moon appears. Keep a clear view toward the eastern horizon — a terrace or balcony helps. If skies are cloudy, note that the computed time is when the Moon is geometrically above the horizon; you may need to wait for it to climb above haze, hills, or buildings before it is actually visible.

Common mistakes to avoid

Do not use a single "all-India" moonrise time you saw online — it can be wrong by up to ~50 minutes for your city. Do not confuse moonrise with sunset; the Moon rises well after the Sun sets on Karva Chauth. Remember the computed time is the astronomical moonrise: tall buildings, hills, fog, or smog can delay the visible moon by several minutes to over an hour, so if your tradition requires an actual sighting, treat the time as the earliest possible moment and watch the sky. Finally, make sure you have selected the correct year, since the festival date and the exact moonrise shift from year to year.