The Islamic Hijri calendar is a lunar calendar consisting of 12 months, each beginning with the sighting of the new crescent moon. A Hijri year is approximately 354 days — about 11 days shorter than the Gregorian year. This is why Islamic dates shift earlier each year relative to the Gregorian calendar.

Why the Hijri Calendar Matters

For Muslims, the Hijri calendar is not just a system of date-keeping. It determines:

  • When Ramadan begins and ends
  • The dates of Eid ul Fitr and Eid ul Adha
  • The days of Hajj (8th–13th Dhul Hijjah)
  • The significance of Muharram and Ashura
  • The blessed month of Rajab and the night of Isra wal Miraj
  • When to pay Zakat (if calculating from a Hijri date)

The 12 Months of the Hijri Calendar

  1. Muharram — Sacred month; includes the Day of Ashura (10th)
  2. Safar
  3. Rabi ul Awwal — Birth month of the Prophet (12th)
  4. Rabi ul Thani
  5. Jumada ul Awwal
  6. Jumada ul Thani
  7. Rajab — Sacred month; Isra wal Miraj (27th)
  8. Sha'ban — Shab e Barat (15th)
  9. Ramadan — Month of fasting; Laylat ul Qadr in final 10 nights
  10. Shawwal — Eid ul Fitr (1st); 6 fasts of Shawwal
  11. Dhul Qadah — Sacred month
  12. Dhul Hijjah — Hajj (8th–13th); Eid ul Adha (10th); Day of Arafah (9th)

Converting Between Hijri and Gregorian

Converting dates manually requires complex calculations. The DuaSalaam Islamic Calendar converts any Gregorian date to Hijri instantly and shows all upcoming Islamic events with their significance.

Moon Sighting vs Calculation

There are two main approaches to determining Islamic months:

  • Local moon sighting — Month begins when the crescent is physically sighted in your country
  • Global moon sighting — Month begins when the crescent is sighted anywhere in the world
  • Astronomical calculation — Month is pre-determined by calculation

Different countries and scholars follow different approaches, which is why Eid dates sometimes differ between countries by a day.