The Islamic (Hijri) Calendar

The Islamic calendar is based on the lunar year of about 354 days. The number of days each month is adjusted according to the lunar cycle, beginning about two days after the new moon. The months drift backward over the seasons, returning to their starting points after about 33 lunar years. The Islamic year begins on the first day of Muharram, and is counted from the year of the Hegira (anno Hegirae)—the year in which Muhammad emigrated from Mecca to Medina (A.D. 622). The year 2015 translates to A.H. 1436–1437. The year 2016 translates to A.H. 1437–1438.

Month Number
of days
Muharram 29 or 30
Safar 29 or 30
Rabi I 29 or 30
Rabi II 29 or 30
Jumada I 29 or 30
Jumada II 29 or 30
Rajab 29 or 30
Sha'ban 29 or 30
Ramadan 29 or 30
Shawwal 29 or 30
Dhu'l-Qa'dah 29 or 30
Dhu'l-Hijjah 29 or 30