Home/ Islamic/ Hijri Date Converter

☪️ Hijri Date Converter

Convert dates between the Gregorian calendar and the Hijri (Islamic) calendar in either direction.

Convert a Date

Converted Date

Hijri Date
–
Numeric Format
–
Day of Week
–

This converter uses the tabular (arithmetic) Islamic calendar, which may differ by 1–2 days from local moon-sighting-based dates observed in some regions.

Advertisement

How the Hijri Date Converter Works

The Hijri calendar is a lunar calendar of 12 months totaling 354 or 355 days per year. This tool uses the standard tabular (civil) Islamic calendar, a well-documented arithmetic approximation based on a 30-year cycle with 11 leap years, rather than actual moon sighting.

Formula

Gregorian → Julian Day Number (JDN):
a = floor((14 − month) / 12); y = year + 4800 − a; m = month + 12a − 3
JDN = day + floor((153m + 2)/5) + 365y + floor(y/4) − floor(y/100) + floor(y/400) − 32045

JDN → Hijri:
hijriYear = floor((30 × (JDN − 1948440) + 10646) / 10631)
hijriMonth found by iterating month boundaries from hijriToJD(hijriYear, month, 1)
hijriDay = JDN − hijriToJD(hijriYear, hijriMonth, 1) + 1

Hijri → JDN:
JDN = day + ceil(29.5 × (month − 1)) + (year − 1) × 354 + floor((3 + 11 × year) / 30) + 1948440 − 1

JDN → Gregorian (inverse JDN algorithm):
Standard proleptic Gregorian calendar inversion using floor-division steps.

The tabular calendar places 11 leap years (with a 30th day added to Dhu al-Hijjah) within each 30-year cycle, at years 2, 5, 7, 10, 13, 16, 18, 21, 24, 26, and 29 of the cycle.

Hijri Months

  • 1. Muharram
  • 2. Safar
  • 3. Rabi' al-Awwal
  • 4. Rabi' al-Thani
  • 5. Jumada al-Awwal
  • 6. Jumada al-Thani
  • 7. Rajab
  • 8. Sha'ban
  • 9. Ramadan
  • 10. Shawwal
  • 11. Dhu al-Qi'dah
  • 12. Dhu al-Hijjah

Frequently Asked Questions

Why might this differ from my local mosque's announced date?

This converter uses the tabular (arithmetic) Hijri calendar. Many communities instead confirm the start of a new month through local moon sighting, which can shift the date by a day depending on visibility conditions.

How many days are in a Hijri month?

Hijri months alternate between 29 and 30 days in the tabular calendar, following a fixed 30-year cycle designed to approximate the true lunar cycle of about 29.53 days.

How many days are in a Hijri year?

A standard Hijri year has 354 days, and leap years (11 out of every 30 years) have 355 days, roughly 10-11 days shorter than a Gregorian solar year.

Related Calculators