Islamic Calendar

The Islamic calendar, known as hijri or Hegirian, is still based only on the lunar calendar. Furthermore, the sighting of the new moon determines the start of a month.

If the sky is cloudy and the new moon cannot be seen, the previous month continues for another thirty days until the new month starts.

The practical start of a month, on the other hand, is determined by moon cycle astronomical calculations.

The Islamic period starts on July 16, 622, with the Prophet Muhammad's hegira, or departure into exile from Mecca to Medina.

There are twelve Islamic lunar months, some of which are twenty-nine days long and others which are thirty days long, giving a total of 354 days in the Islamic year.

Of comparison to the Gregorian calendar, the fixed holidays in the Islamic calendar shift “backward” approximately 10 days each year.

Ramadan, the Islamic holy month of fasting, travels back across the full solar year in around 36 years. The Islamic day begins at sunset and ends at sunset.

Other calendars were created in Islamic nations for agricultural purposes, which rely on the solar calendar.

The Coptic calendar, a variant of the Julian calendar, was widely used until recently, but it is currently restricted to Egypt and Sudan, two nations with significant Coptic populations.

The Ottoman Empire utilized the Turkish fiscal calendar, which was likewise Julian-based.

In today's world, the Gregorian calendar is used almost everywhere for civic reasons, whereas the Islamic calendar solely sets religious observance days.