Age in Jewish Hebrew Calendar

Enter your birth date to see your age in the Jewish Hebrew Calendar.

Your Date of Birth (Gregorian) (DD-MM-YYYY)

Lunisolar Calendar (19-Year Metonic Cycle) 3761 BCE (Anno Mundi / Creation of the World)

About the Jewish Hebrew Calendar.

The Jewish calendar dates from the creation year (3761 BCE). Your age in Hebrew years depends on whether your birthday has passed relative to the Hebrew month.

Astronomical & Mathematical Structure

Lunisolar Synchronization & Metonic Intercalation

The Hebrew calendar is an astronomical lunisolar system that harmonizes monthly lunar phases with the annual solar tropical cycle. Its chronological epoch is Anno Mundi ('Year of the World'), traditionally calculated as the biblical creation of the universe dating to 1 Tishrei, corresponding to October 7, 3761 BCE in the proleptic Julian calendar. Ordinary common years comprise 12 lunar months totaling 353, 354, or 355 days. To prevent lunar months from drifting out of alignment with agricultural seasons, the calendar incorporates the 19-year astronomical Metonic cycle (Machzor Katan). In 7 out of every 19 years (specifically years 3, 6, 8, 11, 14, 17, and 19), a 30-day 13th intercalary leap month—Adar I (Adar Aleph)—is inserted before Adar II (Adar Bet), keeping the calendar harmonized with the sun.

Cultural, Religious & Historical Context

Sacred Tradition, Biblically Mandated Festivals & Civil Law

Possessing biblical foundations dating back millennia and codified mathematically by Hillel II in the 4th century CE, the Hebrew calendar governs Jewish religious life globally. It regulates the weekly Shabbat Torah portions, high holy days including Rosh Hashanah and Yom Kippur, the pilgrimage festival of Sukkot, and life-cycle events such as Bar and Bat Mitzvahs and Yahrzeit memorial anniversaries. The lunisolar intercalation mechanism is biblically essential because Passover (Pesach) is explicitly commanded to fall during the spring month (Chodesh HaAviv). In Israel, the Hebrew calendar is recognized alongside the Gregorian calendar as an official state calendar for legal documents, public holidays, and academic calendars.

Gregorian Comparison & Seasonal Alignment

Unlike pure lunar calendars that drift freely across the solar year, the Hebrew calendar's 19-year leap-month system ensures that dates remain locked within a narrow seasonal window. Over 19 years, 235 lunar months equal almost exactly 19 solar years (with an error of only about 1.4 hours per cycle). The Hebrew year number is approximately 3760 or 3761 years ahead of the Gregorian calendar (calculated by adding 3760 prior to Rosh Hashanah in autumn, and 3761 thereafter). Because the calendar is lunisolar, an individual's Hebrew age closely tracks their Gregorian age year-for-year, though specific birth anniversaries vary by up to a month.

Frequently Asked Questions

Q1 What is a Hebrew leap year and why does it add an entire month?

A Hebrew leap year inserts an extra 30-day month called Adar I (Adar Aleph). This occurs 7 times in every 19-year cycle to bridge the ~11-day gap between 12 lunar months and one solar year, guaranteeing that Passover always occurs in the spring as biblically required.

Q2 Why is the Hebrew year number in the 5780s?

The Hebrew calendar numbers years Anno Mundi ('from the creation of the world'), which according to traditional rabbinic calculation began in 3761 BCE. Adding 3760 or 3761 to the contemporary Gregorian year yields the current Hebrew year.