Kabbalah
How to Work Out a Bar or Bat Mitzvah Date
In Jewish law, a boy becomes bar mitzvah at 13 and a girl becomes bat mitzvah at 12 (13 in many Reform and Conservative communities), counted by the Hebrew calendar, not the civil one. So the date starts with the Hebrew birthday, and a few calendar rules decide the rest.
By Soul AtlasPublished 3 min read
Step 1: find the Hebrew birth date
The Hebrew day begins at sunset, not midnight. A child born after sunset on 5 March was born on the Hebrew date that begins that evening. That's why the birth time and place matter. A free Hebrew birthday calculator that uses sunset at the birthplace gets this right.
Step 2: count 13 (or 12) Hebrew years
The coming-of-age falls on the same Hebrew date 13 years later for a boy, or 12 for a girl in Orthodox practice. Because Hebrew years are lunisolar and some have 13 months, that date can land up to a few weeks away from the civil birthday.
The special cases
- Born in Adar in a regular year, and the 13th year is a leap year (with Adar I and Adar II): the common Ashkenazi and Sephardi ruling places it in Adar II.
- Born in Adar I or Adar II of a leap year: the same Adar if the coming-of-age year is also a leap year, or simply Adar if it isn't.
- Born on 30 Cheshvan or 30 Kislev, which some years don't have: many authorities place it on 1 Kislev or 1 Tevet, the next day. Practice varies.
The date and the celebration
Becoming bar or bat mitzvah happens automatically on the date. The service where the young person reads from the Torah is often held on a nearby Shabbat, sometimes months later. Communities and families have their own customs, so always confirm the date with your rabbi.
Common questions
- Is a bar mitzvah on the Hebrew or English birthday?
- The Hebrew birthday, 13 Hebrew years later. The civil date can differ by a few weeks.
- What if my child was born after sunset?
- Then the Hebrew birth date is the next day's date, because the Hebrew day begins at sunset.
- At what age is a bat mitzvah?
- 12 in Orthodox practice; many Reform and Conservative communities hold it at 13.
- Does Soul Atlas calculate the bar mitzvah date?
- Soul Atlas calculates the Hebrew birth date with the sunset rule. Use that date and confirm the coming-of-age date with your rabbi.
Astrology, numerology, Human Design and Kabbalah are symbolic traditions, offered here for reflection and entertainment. Nothing in this guide is a prediction or medical, legal or financial advice. Dates are calculated from planetary positions and given in UTC.
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