The Hijri calendar sets the dates of Ramadan, Eid and many family occasions across the Muslim world. Because it follows the Moon, its dates move through the Gregorian year, which can make planning confusing. This guide explains how it works and how to convert dates with confidence.
To convert a date right now, use our free Hijri to Gregorian converter.
A lunar calendar
The Hijri (Islamic) calendar has 12 months, each beginning with the new crescent moon. A lunar month lasts about 29.5 days, so months have 29 or 30 days, and a year has 354 or 355 days.
Unlike lunisolar calendars, the Hijri calendar never adds a leap month. That is why it drifts against the seasons: every Hijri date arrives about 11 days earlier each Gregorian year, and makes a full circuit of the seasons in about 33 years.
The months
- Muharram
- Safar
- Rabiʻ al-Awwal (Rabiʻ I)
- Rabiʻ al-Thani (Rabiʻ II)
- Jumada al-Ula (Jumada I)
- Jumada al-Akhirah (Jumada II)
- Rajab
- Shaʻban
- Ramadan
- Shawwal
- Dhuʻl-Qiʻdah
- Dhuʻl-Hijjah
Important dates
| Occasion | Hijri date |
|---|---|
| Islamic New Year | 1 Muharram |
| Ashura | 10 Muharram |
| Ramadan begins | 1 Ramadan |
| Eid al-Fitr | 1 Shawwal |
| Day of Arafah | 9 Dhuʻl-Hijjah |
| Eid al-Adha | 10 Dhuʻl-Hijjah |
Sighting versus calculation
There are two ways to decide when a month begins:
- Moon sighting. The month begins when the new crescent is actually seen after sunset. This depends on location and weather, and different countries or communities may begin a month on different days.
- Calculation. The month begins according to astronomical rules. Saudi Arabia’s Umm al-Qura calendar is the best-known calculated Hijri calendar and is widely used for civil dates.
This is why an Eid date announced in one country can differ by a day from another. Our converter uses Umm al-Qura; if your community follows local sighting, allow for a possible one-day difference.
Days begin at sunset
In Islamic tradition, a day begins at sunset. The first night of Ramadan, when the special Taraweeh prayers begin, is the evening before the first day of fasting. When planning around a Hijri date, remember that the occasion may begin the evening before the Gregorian date.
Examples for 2026 (Umm al-Qura)
- 1 Ramadan 1447 AH: February 18, 2026.
- 1 Shawwal 1447 AH (Eid al-Fitr): March 20, 2026.
- October 8, 2026: 27 Rabiʻ II 1448 AH.
Converting dates
To convert a Hijri date to the Gregorian calendar:
- Open the Hijri converter.
- Choose the Hijri year, month and day.
- Read the Gregorian date, and remember a sighting-based date may be a day later.
It works the other way too: enter a Gregorian date to see its Hijri equivalent, which is useful for documents and invitations that give both.
Why Hijri dates matter beyond religious occasions
Hijri dates appear on more than festival calendars. Official documents in several countries carry both Hijri and Gregorian dates, and some government services, school terms and contracts use the Hijri date as the reference. If a document gives only the Hijri date, converting it correctly matters: a residence permit, a visa or a licence that expires on a Hijri date will expire on a specific Gregorian day, and a one-day mistake can be expensive.
When a document gives both dates, check that they match. Where a document was prepared using a different calculation, the two can differ by a day; the issuing authority’s own calendar is the one that counts.
The Hijri year in numbers
- 12 months, alternating roughly between 30 and 29 days.
- 354 days in a common year, 355 in some years, when the last month gets an extra day under calculated calendars.
- About 33 Gregorian years for the calendar to cycle through all the seasons.
- Year 1 AH began in 622 CE. As a rough rule, Gregorian year ≈ Hijri year × 0.97 + 622.
That last rule is a quick sanity check: 1447 × 0.97 + 622 ≈ 2025.6, and 1447 AH did indeed run from mid-2025 to mid-2026.
Planning around Ramadan and Eid
- Set reminders early. Eid celebrations, family visits and travel book up quickly.
- Keep both dates on invitations. Many invitations show the Hijri date with the Gregorian one; keep both in your notes.
- Confirm with your community a few days before, if they follow local sighting.
Invited understands 9 calendar systems, including Hijri, and reads documents in 80+ languages, including Arabic, Urdu and Persian. Snap an invitation with a Hijri date and it becomes a reminder in your calendar.
