How to Use This Calculator
- Select a Gregorian date: Choose any date from the calendar to view its corresponding Islamic date.
- Or input a Hijri date: Select day, Islamic month, and year (AH) to calculate the corresponding Gregorian day.
- Track religious milestones: Use accurate lunar calculations for Ramadan, Zakat hawl, and Eid scheduling.
Formula and Calculation Steps
Astronomical Julian Day Number (JDN) Algorithmic Mapping:
Gregorian Date ⇄ Julian Day Number (JDN) ⇄ Islamic Hijri Date
Lunar Year Duration = ~354.367 Days
Solar Year Duration = ~365.242 DaysWorked Examples and Reference Table
| Islamic Month | Order | Significance |
|---|---|---|
| Muharram | 1st | Sacred month, Day of Ashura (10th) |
| Rabi al-Awwal | 3rd | Mawlid un-Nabi (12th) |
| Rajab | 7th | Sacred month, Isra and Mi'raj (27th) |
| Sha'ban | 8th | Shab-e-Barat / 15th Sha'ban |
| Ramadan | 9th | Obligatory Fasting & Revelation of Quran |
| Shawwal | 10th | Eid al-Fitr (1st) |
| Dhu al-Hijjah | 12th | Sacred month, Hajj pilgrimage & Eid al-Adha |
Frequently Asked Questions
How does the Islamic (Hijri) calendar differ from the Gregorian calendar?
The Hijri calendar is strictly lunar, consisting of 12 lunar months of 29 or 30 days, totaling roughly 354 or 355 days per year. Because it is approximately 10 to 11 days shorter than the solar Gregorian year, Islamic dates cycle backward through the solar seasons every 33 years.
When did the Islamic Hijri calendar begin?
The calendar begins from the Hijrah (migration) of the Prophet Muhammad (peace be upon him) from Makkah to Madinah in 622 CE, designated as Year 1 AH (Anno Hegirae).
Can calculated Hijri dates differ by 1 day from local sightings?
Yes. Algorithmic calendars (such as the Umm al-Qura astronomical standard) calculate theoretical new moon conjunctions. Actual religious observance in specific countries depends upon physical visual crescent moon sightings (Ruet-e-Hilal).
How do I use this converter to calculate my Hawl for Zakat?
Zakat is due once one full lunar year (354 days) elapses on qualifying wealth above Nisab. Use this tool to match your Gregorian financial milestone to its exact Hijri date.
What are the four sacred months in the Islamic calendar?
The four sacred months (Al-Ashhur Al-Hurum) mentioned in the Quran are Dhu al-Qi'dah, Dhu al-Hijjah, Muharram, and Rajab.