Hijri to Gregorian converter
Convert any Islamic (Hijri) date to the Gregorian calendar. Enter the day, the Islamic month, and the year in AH (Anno Hegirae), and the tool shows the matching Gregorian date and the weekday. It is handy for working out the Gregorian date of a birthday, anniversary, or historical event recorded in the Hijri calendar.
How it works
The converter uses the tabular (arithmetic) Islamic calendar, which fixes month lengths by formula rather than by moon sighting. It converts your Hijri date to a Julian Day Number — a continuous count of days that both calendars share — using the standard 30-year cycle in which 11 years are leap years, then converts that day number back into a Gregorian year, month and day, and derives the weekday. The result is exact and reproducible. Because the religious calendar can depend on a local moon sighting, the actually observed date may differ by about a day.
Example
The Hijri date 1 Ramadan 1447 AH converts to roughly 18 February 2026 in the tabular calendar. The tool also shows the weekday for that Gregorian date.
| Hijri month | Note |
|---|---|
| Muharram | First month |
| Ramadan | Month of fasting |
| Dhu al-Hijjah | Hajj; 30 days in leap years |
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The twelve months of the Hijri calendar
The Islamic year has twelve months with alternating 30- and 29-day lengths in the standard tabular pattern:
| Month | Days (common year) | Significance |
|---|---|---|
| Muharram | 30 | Islamic New Year; Ashura on 10 Muharram |
| Safar | 29 | |
| Rabi al-Awwal | 30 | Birth of the Prophet (Mawlid) |
| Rabi al-Thani | 29 | |
| Jumada al-Ula | 30 | |
| Jumada al-Thani | 29 | |
| Rajab | 30 | Sacred month |
| Shaban | 29 | Precedes Ramadan |
| Ramadan | 30 | Month of fasting |
| Shawwal | 29 | Eid al-Fitr on 1 Shawwal |
| Dhu al-Qadah | 30 | Sacred month |
| Dhu al-Hijjah | 29 (30 in leap years) | Hajj; Eid al-Adha on 10 Dhu al-Hijjah |
In leap years the 30-year cycle extends the final month by one day to 30, giving a year of 355 days rather than 354.
Why the Islamic calendar drifts through the Gregorian seasons
Because the Hijri year is approximately 11 days shorter than the Gregorian solar year, Islamic dates advance through the Gregorian calendar at that rate every year. Over roughly 33 years the two calendars complete a full cycle, and any given Islamic date will have occurred in every Gregorian month during that time. This is why Ramadan falls in summer some years and in winter others, and why it eventually returns to roughly the same Gregorian dates after about 33 years.
Arithmetic vs. observational calendars
This tool uses the tabular (arithmetic) calendar, which determines dates by calculation and is used for civil planning, historical research, and software. The observational calendar determines the start of months by the actual sighting of the crescent moon, which can differ by a day or two from the tabular result depending on local horizon conditions, weather, and the criteria used by religious authorities. For religious observance, always defer to the announcement from the relevant local or national authority rather than relying solely on a calculated result.