Hijri to Gregorian Date Converter: How the Islamic Calendar Works (2026)
The Hijri (Islamic) calendar starts from a different year, runs on a different cycle, and has 12 months that don’t match Gregorian months. Converting between the two is something Muslims need to do regularly — for birthdays, anniversaries, religious events, and historical dates. The tool below does it in either direction. Read on to understand how the calendar works and why dates sometimes differ by a day.
What Is the Hijri Calendar?
The Hijri calendar is a lunar calendar with 12 months totaling 354 or 355 days per year — about 11 days shorter than the Gregorian (solar) year. Each month begins with the sighting of the new crescent moon and lasts 29 or 30 days.
The calendar’s epoch (year 1) is the year of the Hijrah — Prophet Muhammad’s migration ﷺ from Mecca to Medina in 622 CE. Year 1 of the Hijri calendar corresponds roughly to 622–623 CE.
“AH” after a Hijri year stands for Anno Hegirae (“in the year of the Hijra”). So 1447 AH means “year 1447 since the Hijra.”
The 12 Hijri Months
- Muharram — sacred month; contains the Day of Ashura (10 Muharram)
- Safar
- Rabi’ al-Awwal — contains Mawlid an-Nabi (12 Rabi’ al-Awwal in many traditions)
- Rabi’ al-Thani
- Jumada al-Awwal
- Jumada al-Thani
- Rajab — sacred month; contains Isra and Mi’raj (27 Rajab)
- Sha’ban — contains Laylat al-Bara’ah (15 Sha’ban)
- Ramadan — month of fasting
- Shawwal — begins with Eid al-Fitr (1 Shawwal)
- Dhu al-Qi’dah — sacred month
- Dhu al-Hijjah — sacred month; contains Hajj and Eid al-Adha (10 Dhu al-Hijjah)
Four of these — Muharram, Rajab, Dhu al-Qi’dah, and Dhu al-Hijjah — are known as the “sacred months,” during which warfare was historically prohibited and the reward for good deeds is considered greater.
Why Hijri Dates “Move Backwards” Every Year
Because the lunar year is 11 days shorter than the solar year, Islamic events shift earlier in the Gregorian calendar each year:
- Ramadan 2025 began around March 1
- Ramadan 2026 began around February 17–18
- Ramadan 2027 expected around February 7–8
- Ramadan 2028 expected around late January
Over a 33-year cycle, Ramadan passes through every season — long summer days, short winter days, and everything in between. This is by design. The Hijri calendar follows the moon, not the sun, so it doesn’t sync with the Earth’s seasons.
How Hijri-to-Gregorian Conversion Works
There are two approaches:
1. Tabular (calculated) conversion
Uses a mathematical formula that approximates the Hijri calendar’s behavior over centuries. Each year has a fixed pattern of 354 or 355 days, and the algorithm distributes 29- and 30-day months systematically.
The most common is the Kuwaiti algorithm (a tabular variant), which is what the converter below uses. Other tabular variants include the Civil (Microsoft) algorithm and the Astronomical algorithm. All give results within ±1 day of each other for most dates.
2. Observational (moon-sighting) conversion
The “true” Hijri calendar is determined by actual moon-sighting in each region. A month begins only when the crescent is confirmed sighted on the evening of the 29th day of the previous month. If no sighting, the previous month becomes 30 days.
This means the real Hijri date in your country can differ by 1 day from any calculated version. Some countries (Saudi Arabia officially uses the Umm al-Qura calendar) have their own published calendars; others wait for local sightings.
Which to use
For most practical purposes — birthdays, anniversaries, historical dates — the calculated version is fine. For determining the exact start of Ramadan or Eid in your country, defer to your local Islamic authority’s announcement.
Use the Hijri Date Converter
Convert any date in either direction. Enter a Gregorian date to get its Hijri equivalent, or a Hijri date to get its Gregorian equivalent.
Hijri ↔ Gregorian Converter
Convert between the Islamic (Hijri) and Gregorian calendars
Note: Hijri dates are based on calculated (Umm al-Qura) astronomical conversion. Actual sighting of the moon may shift the date by ±1 day depending on your country's official calendar.
Common Uses for Hijri Date Conversion
- Finding your Hijri birthday. Many Muslims like to know their Islamic-calendar birthday. Enter your Gregorian birthdate to get the Hijri equivalent.
- Setting your zakat anniversary. Zakat is owed annually on the Hijri date your wealth first crossed nisab. Most people pick a fixed Hijri date (like 1 Ramadan) and use it consistently.
- Anniversary dates. Wedding or other family anniversaries that you want to track on both calendars.
- Researching historical Islamic events. Most Islamic historical sources use Hijri dates; converting to Gregorian helps place them in modern context.
- Planning around upcoming events. If you know Ramadan starts at 1 Ramadan 1448 AH, convert to find the Gregorian date for travel planning, work leave, etc.
Quick Reference: Recent and Upcoming Years
Approximate Gregorian start of each Hijri year (1 Muharram):
- 1446 AH — July 7, 2024
- 1447 AH — June 26, 2025
- 1448 AH — June 16, 2026
- 1449 AH — June 5, 2027
- 1450 AH — May 25, 2028
These dates are calculated using the tabular algorithm; the actual observed start in your country may shift by ±1 day.
Why Dates Differ by ±1 Day
You might convert a Hijri date in our tool and get a Gregorian date that’s a day off from what your family elder remembers, or what a different calendar app shows. Several reasons this happens:
- Different tabular algorithms distribute the 29/30-day months slightly differently.
- Observational vs calculated calendars disagree. Saudi Arabia’s official Umm al-Qura calendar uses calculation; other countries use moon-sighting and may differ by a day.
- Country-by-country variation. The same Hijri date can be different Gregorian dates in Saudi Arabia, Pakistan, Indonesia, and Egypt, because each country uses its own moon-sighting methodology.
- Edge cases at month boundaries. If you converted a date right at the start or end of a Hijri month, the ambiguity is largest.
For most personal uses (birthdays, anniversaries), a ±1 day discrepancy doesn’t matter. For religious events with specific timing (start of Ramadan, Eid, Hajj), defer to your local authority’s announcement, not a calculator.
Sources and Scholarly Notes
This guide draws on:
- The Qur’an, particularly Surah At-Tawbah (9:36) on the twelve months in Allah’s sight.
- Reingold and Dershowitz, “Calendrical Calculations” — the standard academic reference for calendar algorithms.
- The Umm al-Qura calendar as adopted by the Kingdom of Saudi Arabia.
- The Kuwaiti algorithm for the tabular Islamic calendar (used in this tool’s calculations).
For religious events with specific timing — Ramadan start, Eid, Hajj — defer to your local mosque or Islamic authority’s announcement rather than relying solely on calculated dates.
Disclaimer: Calculated Hijri dates are mathematical approximations and may differ from official observed dates in your country by ±1 day. For most uses (birthdays, anniversaries) this is fine; for religious events requiring exact timing, defer to local authority.
Related Tools
- Islamic Events Calendar — major Islamic dates for the current year
- Prayer Times — daily salah times for your location
- Ramadan Timer — countdown to suhoor and iftar
- Qibla Finder — find the direction of the Kaaba
- Zakat Calculator — calculate your annual zakat
Frequently Asked Questions
Q: What year is it in the Hijri calendar?
A: As of May 2026, we’re in the year 1447 AH (Anno Hegirae), with 1448 AH beginning around June 16, 2026. The exact day depends on moon-sighting.
Q: Why is the Hijri calendar 11 days shorter than the Gregorian calendar?
A: The Hijri calendar follows the moon — each month is one lunar cycle (29 or 30 days). The Gregorian calendar is solar, syncing with the Earth’s orbit around the sun. A lunar year is 354 days; a solar year is 365 days.
Q: When does Ramadan 2027 start?
A: Ramadan 1448 AH is expected to begin around February 7–8, 2027, depending on local moon-sighting. The exact day will be confirmed by your country’s Islamic authority closer to the time.
Q: My Hijri birthday changes every year on the Gregorian calendar. How do I track it?
A: Your Hijri birthday (e.g., 12 Rajab 1410) is fixed in the Hijri calendar — that day comes once a year. The corresponding Gregorian date shifts back ~11 days each year. Use the converter to find this year’s equivalent.
Q: Are Hijri dates the same in every country?
A: Not always. Saudi Arabia uses the Umm al-Qura calendar (calculated). Other countries use local moon-sighting. The same Hijri date can fall on different Gregorian dates in different countries, usually by ±1 day.
Q: How accurate is this converter?
A: The converter uses the tabular Islamic calendar (Kuwaiti algorithm), which is mathematically precise for the algorithm itself. Actual moon-sightings in your country may differ by ±1 day. For most uses (anniversaries, planning), the converter is more than sufficient.
Q: What does “AH” mean?
A: “AH” stands for Anno Hegirae (Latin for “in the year of the Hijra”). It marks years since Prophet Muhammad’s ﷺ migration from Mecca to Medina in 622 CE.
Q: Why do Eid dates differ between countries?
A: Eid al-Fitr is the 1st of Shawwal — which begins when the crescent moon is sighted ending Ramadan. Different countries use different moon-sighting methodologies, so Eid can fall on different Gregorian days. Saudi Arabia announces officially based on Umm al-Qura; other countries make their own announcements.