What is the twelve tribes calendar months?
Hebrew names of the months with their Babylonian analogs Number Hebrew name Length Babylonian analog Notes 1 Nisan / Nissan 30 days Nisanu called Aviv in the Tanakh 2 Iyar 29 days Ayaru called Ziv in the Tanakh 3 Sivan 30 days Simanu 4 Tammuz 29 days Du’uzu 5 Av 30 days Abu 6 Elul 29 days Ululu 7 Tishrei 30 days Tashritu called Eitanim in the Tanakh 8 Cheshvan 29 or 30 days Arakhsamna also spelled Heshvan; called Bul in the Tanakh 9 Kislev 30 or 29 days Kislimu also spelled Chislev 10 Tevet 29 days Tebetu 11 Shevat 30 days Shabatu 12* Adar I* 30 days Adaru *Only in leap years 12 / 13* Adar / Adar II* 29 days During leap years Adar I (or Adar Aleph — “first Adar”) is considered to be the extra month, and has 30 days. Adar II (or Adar Bet — “second Adar”) is the “real” Adar, and has 29 days as usual. For example, in a leap year, the holiday of Purim is in Adar II, not Adar I.
