Hijri Date Converter Widget

How it works

Modern browsers ship the Unicode CLDR calendar data, which includes the Umm al-Qura calendar of Saudi Arabia under the identifier islamic-umalqura. The widget asks the browser to format a Gregorian date in that calendar, which gives the Hijri day, month and year with no table of our own to go stale. The reverse direction makes an arithmetic estimate from the Islamic epoch (16 July 622 Julian) and a mean month of 29.5306 days, then checks the days around it until the browser's own mapping matches, so both directions always agree. If the chosen month has only 29 days, asking for day 30 is refused with the month's real length. Umm al-Qura months start when, at Mecca on the 29th, conjunction has occurred before sunset and the Moon sets after the Sun; that astronomical rule does not depend on anyone sighting the crescent, so moon-sighting communities may start a month one day later. The supported range is 1356-1500 AH (14 March 1937 to 16 November 2077).

Method

• Gregorian to Hijri: Intl.DateTimeFormat('en-u-ca-islamic-umalqura') day, month and year at 12:00 UTC
• Hijri to Gregorian: estimate = epoch (16 July 622 Julian) + (year - 1) x 354.36667 + (month - 1) x 29.530589 + day - 1 days, then search +/- 25 days for the exact match
• Month length = start of next month - start of this month (29 or 30 days)
• Umm al-Qura month start (since 1423 AH): on the 29th, conjunction before sunset at Mecca and moonset after sunset, else the month has 30 days

Worked examples

Calculated Umm al-Qura dates for guidance. Religious observances that begin with a local moon sighting can fall a day earlier or later; follow your local mosque or authority.

Limitations

• Only the Umm al-Qura calendar; moon-sighting, Diyanet and MABIMS dates can differ by a day.
• Limited to 1356-1500 AH (1937-2077), the range of the published table the conversion was checked against.
• Needs a browser with the CLDR Umm al-Qura calendar; very old browsers show a message instead of a date.

Where publishers use it

• Mosque and Islamic centre websites showing the Hijri date beside event listings
• Gulf-region business sites where contracts and documents are dated in both calendars
• Hajj and Umrah travel agents converting departure dates for pilgrims
• Islamic school portals planning terms around Ramadan and the two Eids
• Genealogy and history blogs converting Hijri dates found on old documents

Questions

Sources

1. Official Umm al-Qura calendar - Umm al-Qura calendar website, Saudi Arabia . The official site of the calendar the widget follows. Checked 2026-10-01.
2. The Umm al-Qura Calendar of Saudi Arabia - R.H. van Gent, Utrecht University . Rules by period (calculated at KACST, current rule since 1423 AH) and a month-start table for 1356-1500 AH used to verify the test dates. Checked 2026-10-01.
3. CLDR BCP 47 calendar identifiers (calendar.xml) - Unicode CLDR . Defines islamic-umalqura as "Hijri calendar, Umm al-Qura", the calendar the browser's Intl API exposes. Checked 2026-10-01.

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A2Z Tools Hijri Date Converter
https://a2z.tools/embed/hijri-date-converter

<a href="https://a2z.tools/embed/hijri-date-converter">A2Z Tools Hijri Date Converter</a>

[A2Z Tools Hijri Date Converter](https://a2z.tools/embed/hijri-date-converter)

Hijri Date Converter by A2Z Tools - https://a2z.tools/embed/hijri-date-converter