Purnima, the full Moon, and Amavasya, the new Moon, mark the two ends of the lunar fortnight, and both are kept as observance days in many households: a fast, a bath at dawn, an offering to ancestors or a visit to the temple. Both are tithis, spans of time that begin and end at any hour, so the question “which day is it?” does not always have one obvious answer. This tool gives the next Purnima and the next Amavasya for your city, with the day to keep each and the times between which the tithi runs.
What you see
At the top are two answers side by side: the next Purnima and the next Amavasya after the date you chose, each with its month name and the exact times the tithi begins and ends in local time. Below them are two tables with the next six of each. For every tithi the tables show the vrat day, the begin and end times, and the snan and daan day if it differs, which is the day when the tithi is present at sunrise and so suits a dawn bath and charity.
How the day is chosen
A tithi is the time the Moon takes to gain twelve degrees on the Sun, so it is not tied to the clock. Purnima begins when the Moon is 168 degrees ahead of the Sun and ends when it is 180 degrees ahead; Amavasya runs from 348 to 360 degrees. The engine on this site works out those moments from the Swiss Ephemeris tables and then asks which civil day the tithi belongs to.
For the Purnima vrat, the day is the one on which Purnima is present at Madhyahna, the middle of the day. For the Amavasya vrat, it is the day on which Amavasya is present at Aparahna, the afternoon, which is the time associated with ancestor rites. The snan and daan day, when it differs, is the day the tithi is present at sunrise. Many families keep the dawn bath on that day and the evening observance on the vrat day.
Month names
The name given beside each Purnima, for example Kartika Purnima, is the purnimanta name used by most North Indian calendars. The same Purnima ends the month in that system, which is why it shares the name of the month it closes. The amanta system, followed in Gujarat, Maharashtra and the south, starts counting the dark half in the next month. The two systems agree on the bright half and differ on the dark half, and the guide to amanta and purnimanta months explains the difference.
Why two cities can differ
The Moon’s position is the same everywhere at the same instant. The sunrise, the midday and the clock are not. A Purnima that ends shortly after sunrise in Delhi may still be running at sunrise in London, so the two cities can call it different days. A tithi that begins late in the evening and ends the next afternoon belongs to the second day by the sunrise rule even though it starts on the first. The tool uses your city’s own sunrise and the time zone in force there on that date, daylight saving included, and says so under the table.
Where traditions differ
Some families keep the fast on the day the tithi is present at sunrise whatever the time of day, and some on the day it is present in the evening, when the Moon is seen. Temples often follow their own panchang. If your family follows a particular almanac, keep to it, and use this tool to see the tithi times and to understand why the dates move. The tool does not predict what a day will bring and carries no promise of results from any observance.
To go further, read about Purnima vrat, Amavasya and the tithis themselves on the Purnima and Amavasya pages, or look up any festival in any city on the festival dates tool.
Frequently asked questions
↳ Why is the Purnima date different from the full Moon in a diary?
A diary usually marks the moment of the exact full Moon. A panchang gives the tithi, which runs for some hours either side, and assigns it to a day by sunrise or midday rules.
↳ Which day do I fast, the vrat day or the snan day?
The vrat day is the one the panchang rule gives for the fast. The snan and daan day is the one on which the tithi is present at sunrise. Follow your family's custom where they differ.
↳ Why does the table sometimes show the same day for both?
When the tithi is present both at sunrise and at midday, or at sunrise and in the afternoon, one day serves for both, and the table says Same day.
↳ Are the times in my time zone?
Yes. They are on the clock of the city you choose, with daylight saving applied where it was in force on that date.
↳ Is Amavasya inauspicious?
Many families treat it as a quiet day set aside for ancestors, charity and reflection rather than new beginnings. It is a custom, not a prediction about anyone's day.