Resource
Hijri Date Conversion Method Guide: Umm al-Qura, Browser Intl and Moon-Sighting Limits
A method guide for the Muslim Post Hijri Date Converter, explaining the Umm al-Qura calendar, browser Intl formatting, reverse lookup and local moon-sighting limits.
Calendar used
islamic-umalqura
Engine
Browser JavaScript Intl.DateTimeFormat
Reverse lookup
Searches nearby Gregorian dates
Boundary
Local moon-sighting may differ by one day
The Hijri Date Converter is built for transparent reference, not for declaring the start of a religious month in every community. Quran 2:185 connects Ramadan with the month and its witness, while this web tool uses a browser calendar system to produce a stable planning date.
Muslim Post uses the `islamic-umalqura` calendar through JavaScript Intl formatting. Gregorian-to-Hijri conversion formats a UTC civil date at noon and reads the Hijri year, month and day from formatted parts. Hijri-to-Gregorian conversion searches a nearby Gregorian range until the requested Hijri date appears.
That method is deterministic for the browser environment, which is good for calculators, archive pages and planning. It is not the same as a local moon-sighting announcement, and it may differ by a day from communities that follow visible sighting or a different national calendar.
Use this guide before comparing dates from different apps. When two calendars disagree, record the method first: Umm al-Qura browser calendar, local mosque announcement, national authority, or observed moon-sighting.
Hijri Conversion Method Boundaries
| Feature | Tool behavior | Useful for | Boundary |
|---|---|---|---|
| Gregorian to Hijri | Formats a UTC civil date using islamic-umalqura. | Daily lookup and planning. | Not a moon-sighting announcement. |
| Hijri to Gregorian | Searches nearby Gregorian dates until the Hijri parts match. | Finding an approximate civil date. | Invalid or out-of-range Hijri dates return no result. |
| Month names | Uses localized Intl calendar formatting. | Showing Hijri month names in supported languages. | Browser locale support can vary. |
| Religious dates | Provides stable planning dates. | Calendars, archives and reminders. | Follow local authority for Ramadan or Eid announcements. |
FAQ
Why can Hijri dates differ by one day?
Different calendars, local moon-sighting decisions, time zones and browser calendar data can produce a one-day difference.
Should I use this converter for Ramadan announcements?
Use it for planning and comparison. For Ramadan start, Eid and community practice, follow your local mosque or recognized authority.
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Languages
- دليل تحويل التاريخ الهجري: تقويم أم القرى وواجهة Intl وحدود رؤية الهلال
- Průvodce: hidžra datum
- Guide til Hijri dato
- Leitfaden zu Hijri Datum
- Οδηγός για Hijri ημερομηνία
- Hijri Date Conversion Method Guide: Umm al-Qura, Browser Intl and Moon-Sighting Limits
- Opas: Hijri päivämäärä
- Guide de hégirien date
- Panduan Hijriah tanggal
- ガイド: ヒジュラ暦 日付
- 가이드: 히즈리 날짜
- Panduan Hijri tarikh
- Gids voor Hijri datum
- Veiledning om Hijri dato
- Przewodnik po hidżri data
- Руководство по теме Hijri дата
- Sprievodca: hidžra dátum
- Guide till Hijri datum
- คู่มือ ฮิจเราะห์ วันที่
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- Hướng dẫn về Hijri ngày
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