Famouse algorithm & Kuwaiti algorithm for Islamic Calendar

 

Famouse algorithm
Word and famouse this algorithm calendar as using this rule the leap years are:
2, 5, 7, 10, 13, 16, 18, 21, 24, 26 and 29.

According to this famouse algorithm to day is: 23 Muharram 1434

Kuwaiti algorithm

The "Kuwaiti algorithm" is used by Microsoft to convert between Gregorian calendar dates and Islamic calendar dates.

Kuwaiti algorithm of the Tabular Islamic calendar as using this rule the leap years are:
2, 5, 7, 10, 13, 15, 18, 21, 24, 26 and 29.

Month in Islam

Important dates in the Islamic (Hijri) year are:

• 1 Muharram (Islamic New Year)
  10 Muharram (Day of Ashura) For Sunni Muslims, the crossing of the Red Sea by Moses (Musa). For all muslims, the martyrdom of Husayn ibn Ali, the grandson of Muhammad, and his followers.
  12 Rabi al Awal (Mawlid an Nabi for majority of Sunnis)
  17 Rabi al Awal (Mawlid an Nabi for Twelvers and some Sunnis)
  27 Rajab (Isra and Mi'raj for majority of Muslims)
  15 Sha'ban (Mid-Sha'ban, or Night of Forgiveness), and for Twelvers the birthday of Muhammad al-Mahdi (The Twelfth Imam)
  1 Ramadan (First day of fasting)
  27 Ramadan (Nuzul Al-Qur'an) The day Muhammad received the first verses of the Qur'an (17 Ramadan in Indonesia and Malaysia)
  Last third of Ramadan which includes Laylat al-Qadr
  1 Shawwal (Eid ul-Fitr)
  8-13 Dhu al-Hijjah (the Hajj to Mecca)
  9 Dhu al-Hijjah (Day of Arafa)
  10 Dhu al-Hijjah (Eid al-Adha)
  

Convert Hijri to civil date or civil to Hijri date

This table may be extended since every nineteen years the Muslim month number increases by seven. When it goes above twelve, subtract twelve and add one to the year AH. From AD412 to AD632 inclusive the month number is 1 and the calculation gives the month correct to a month or so. AD622 corresponds to BH1 and AH1. For earlier years, year BH = (623 or 622) - year AD).

Current correlations

Because a hijri or Islamic lunar year is between 10 and 12 days shorter than a civil year, it begins 10–12 days earlier in the civil year following the civil year in which the previous hijri year began. Once every 33 or 34 hijri years, or once every 32 or 33 civil years, the beginning of a hijri year (1 Muharram) coincides with one of the first ten days of January. Subsequent hijri New Years move backward through the civil year back to the beginning of January again, passing through each civil month from December to January.