Hebrew Birthday Calculator
Enter your date of birth to find your Hebrew birth date and the Gregorian dates of your next Hebrew birthdays.
Wednesday, 15 March 2000, before sunset.
Hebrew date to Gregorian
How the Hebrew calendar works
The Hebrew calendar is lunisolar. Months follow the moon (29 or 30 days), and a thirteenth month, Adar I, is added in 7 years of every 19 so that Pesach stays in spring. Two months, Cheshvan and Kislev, change length from year to year so that Rosh Hashana does not fall on certain weekdays. As a result a Hebrew year has between 353 and 385 days, and a Hebrew date moves around the Gregorian calendar by up to a month.
A Hebrew day runs from nightfall to nightfall. Someone born on a Tuesday evening after sunset was born, by the Hebrew calendar, on Wednesday’s date. Tick the after-sunset box in that case. If the time was close to sunset, check the local sunset time for that date, or ask your rabbi.
Our conversions use the fixed arithmetic of the Hebrew calendar as set out in Reingold and Dershowitz, Calendrical Calculations, and are tested against the open-source Hebcal library for every day from 1800 to 2239.
When a Hebrew birthday date does not exist
- Born in Adar in an ordinary year. In a leap year there are two Adars. The calculator uses Adar II, which is the usual practice for birthdays and Bar/Bat Mitzvahs. Someone born in Adar I or Adar II of a leap year keeps that month when the next year is also a leap year.
- Born on 30 Adar I. In an ordinary year Adar has only 29 days, so the birthday moves to 1 Nisan.
- Born on 30 Cheshvan or 30 Kislev. In years when that month has 29 days, the birthday moves to the 1st of the next month.
These are the rules in Calendrical Calculations. Some families follow a different custom, especially for Adar; if the date matters for a ceremony, confirm it with your rabbi.