The Jewish or Hebrew calendar is governed by a relatively complex set of rules and stipulations dating back to year one, which is estimated to be in the year 3761 BC. This was established as the biblical Date of Creation by Maimonides.

The calendar is a lunisolar calendar, meaning that the months are based on the cycles of the moon, while the year is based on the cycle of the sun. In the Hebrew calendar, a new day begins at sunset, and a month begins on the new moon, which is observed as Rosh Chodesh, or “the head of the month.” As the lunar months do not perfectly align to a solar year, an additional lunar month (or “leap month”) is added to the calendar in 7 out of every 19 years so that the major holidays and festivals occur in their proper season. It is for this reason that the Jewish holidays fall on different dates in the Gregorian (January-December) calendar each year.

The months of the Jewish/Hebrew Calendar and the Gregorian months in which they may fall are:

Nisan (March/April/May)

Iyar (April/May/June)

Sivan (May/June/July)

Tammuz (June/July/August)

Av (July/August/September)

Elul (August/September/October)

Tishrei (September/October/November)

Cheshvan (October/November/December)

Kislev (November/December)

Tevet (December/January)

Shevat (January/February)

Adar I – Occurs only in leap years (January/February/March)

Adar or Adar II in leap years (February/March/April)