তারিখ রূপান্তরক
তারিখগুলি Umm al-Qura (Saudi) মানদণ্ডের উপর ভিত্তি করে এবং 1-2 দিন পরিবর্তিত হতে পারে।
About Hijri-Gregorian Date Conversion
Converting between the Islamic Hijri calendar and the Gregorian calendar requires more than simple arithmetic. The Hijri calendar is purely lunar — each month begins with the sighting of the new crescent moon and lasts 29 or 30 days, making the year approximately 354 days long. This 11-day difference from the Gregorian year means Hijri dates continuously shift relative to Gregorian dates, cycling through all seasons over about 33 years.
Zaman's date converter uses astronomical new moon calculations to determine when each Hijri month begins, then applies the crescent visibility criterion you've selected in your settings. This means the conversion accounts for the actual lunar cycle rather than using a simplified arithmetic approximation, giving you results that match your local authority's calendar.
You can convert in both directions — Gregorian to Hijri and Hijri to Gregorian. After conversion, any Islamic events or festivals falling on the resulting Hijri date are automatically displayed, making it easy to check whether a particular date coincides with Ramadan, Eid, or other significant occasions.
Lunar vs. Solar Calendars
The fundamental difference between the Hijri and Gregorian calendars lies in what they track. The Gregorian calendar follows Earth's orbit around the sun (365.25 days), keeping seasons fixed to the same months each year. The Hijri calendar follows the moon's orbit around Earth (29.53 days per lunation), meaning Islamic months are not tied to any particular season.
This is by design: the Quran and Islamic tradition tie religious observances to the lunar cycle, ensuring that obligations like fasting in Ramadan are experienced in all seasons over a generation. A Muslim born in a particular year will experience Ramadan in summer, winter, spring, and autumn throughout their lifetime — sharing the varying difficulty of fasting across all climates and daylight conditions.
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Frequently Asked Questions
How do I convert a Gregorian date to Hijri?▾
Select "Gregorian to Hijri" mode in the converter above, enter the day, month, and year, and tap Convert. Zaman uses astronomical new moon calculations combined with your selected crescent visibility criterion to determine the corresponding Hijri date. The result includes the Hijri day, month name, and year, plus any Islamic events that fall on that date.
How do I convert a Hijri date to Gregorian?▾
Select "Hijri to Gregorian" mode, enter the Hijri day, month, and year, and tap Convert. The converter will show the equivalent Gregorian date based on astronomical calculations. Note that the exact Gregorian date may differ by 1–2 days depending on the crescent visibility criterion used, since different Islamic authorities may mark the start of a Hijri month on slightly different days.
Why do Hijri-Gregorian conversions sometimes differ by 1–2 days?▾
The Hijri calendar is based on the sighting of the new crescent moon, and different Islamic authorities use different visibility criteria. The Umm al-Qura calendar (Saudi Arabia), ISNA (North America), MABIMS (Southeast Asia), and other methods may predict crescent visibility on different days. Weather conditions and local horizon can also affect actual sighting. This means the same Hijri date may correspond to different Gregorian dates depending on which criterion you follow.
What crescent criterion should I use for date conversion?▾
Use the criterion followed by your local Islamic authority or community. If you're in Saudi Arabia, Umm al-Qura is standard. In North America, ISNA is common. In Southeast Asia, MABIMS is widely used. In Turkey, the Diyanet criterion applies. Zaman lets you switch between criteria in Settings — the converter and calendar will automatically update to match. When in doubt, consult your local mosque or Islamic organization.
Can I find out what Islamic events fall on a specific date?▾
Yes. After converting any date, the converter shows all Islamic events and festivals that fall on the resulting Hijri date. This includes major events like the start of Ramadan, Eid al-Fitr, Eid al-Adha, the Day of Arafah, Ashura, Mawlid an-Nabi, Isra Mi'raj, and other significant dates in the Islamic calendar.
How far back and forward can I convert dates?▾
Zaman's converter supports a wide range of Hijri years for date conversion. The astronomical algorithms used can accurately calculate new moon positions across centuries. For historical research, genealogy, or planning future events, you can convert dates well beyond the current year in either direction.
What is the Hijri calendar epoch?▾
The Hijri calendar begins from the Hijra — Prophet Muhammad's ﷺ migration from Mecca to Medina in 622 CE. Year 1 AH (After Hijra) corresponds to approximately July 622 CE in the Gregorian calendar. The calendar was formally adopted during the caliphate of Umar ibn al-Khattab to standardize date-keeping across the Muslim world. All Hijri dates count forward from this starting point.