Date Difference Calculator
29 days
Gregorian difference: 0 years, 1 months, 1 days
Pre-filled default example: from the start of Ramadan to Eid al-Fitr this year
Date Difference Calculator
This calculator works out the period between two Gregorian dates precisely: the total number of days, the breakdown in years, months and days in the Gregorian calendar, and the equivalent breakdown in Hijri years, months and days per the official Umm al-Qura calendar. The form above is pre-filled with a ready example: from the start of Ramadan to Eid al-Fitr this year (exactly 29 days).
The two results differ because a Hijri year has 354 or 355 days while a Gregorian year has 365 or 366: roughly every 33 Gregorian years match 34 Hijri years, so Hijri years gradually run ahead of their Gregorian counterparts.
When is a date difference useful?
Muslims use date differences for many practical purposes: Hijri age, the waiting period (iddah) in personal-status matters, contracts and official wording in both calendars, the gap between two marriages or two contracts, and the time remaining until an upcoming occasion such as Ramadan, Hajj or the two Eids.
Two-calendar comparison matrix
There is no fixed ratio between the two calendars because a Hijri year has 354 or 355 days; however, the correspondence can be approximated using the mean Hijri year (about 354.37 days). The table below shows common Gregorian spans and their approximate equivalent in Hijri years:
| Gregorian span | Gregorian days (approx.) | Equivalent Hijri years (approx.) |
|---|---|---|
| 1 year | ~365 | ~1.03 |
| 5 years | ~1826 | ~5.15 |
| 10 years | ~3652 | ~10.31 |
| 20 years | ~7305 | ~20.61 |
| 33 years | ~12053 | ~34.01 |
| 50 years | ~18262 | ~51.54 |
Values are approximations for general understanding and planning; for the exact difference between two specific dates use the calculator at the top of the page, which follows the official Umm al-Qura table day by day.
Caution: the Hijri day starts at sunset, not at midnight
The day in the Hijri calendar begins, both legally and traditionally, at sunset (maghrib), while the Gregorian day begins at midnight. So if you travel or carry out a calculation between one evening and the next day, the Hijri date may already have advanced by a full day while the Gregorian date has not — this is the most common source of confusion when converting between the two calendars around the evening on which the Hijri date changes. When comparing this calculator’s results with official records or documents, make sure both sides agree on the day’s starting point: sunset or midnight.
Frequently asked questions
How do I calculate the difference between two dates?
Enter the first and second dates in the picker above and press “Calculate difference”. The site shows the total number of days and the breakdown in years, months and days in both the Gregorian and Hijri calendars.
Why does the Hijri difference differ from the Gregorian one?
A Hijri year has 354 or 355 days while a Gregorian year has 365 or 366, so the same period contains more Hijri years than Gregorian years, a full extra year roughly every 33 Gregorian years.
What date range is supported?
Calculations cover Gregorian dates from November 12, 1882 to November 16, 2077, the range of the official Umm al-Qura table (1300–1500 AH).