About the Islamic Hijri Calendar
The Hijri calendar is the primary calendar used throughout the Muslim world for religious observances. Unlike the Gregorian solar calendar, it follows the lunar cycle — each month begins with the sighting of the new crescent moon and lasts 29 or 30 days. The calendar consists of 12 months totaling 354 or 355 days per year.
Zaman's interactive Hijri calendar lets you browse months in both Hijri and Gregorian views, see Islamic events and festivals marked on each day, and switch between crescent visibility criteria (Umm al-Qura, ISNA, MABIMS, and more) to match your local authority. All dates are calculated using astronomical new moon data and the criterion you select in your settings.
The four sacred months — Muharram, Rajab, Dhul Qa'dah, and Dhul Hijjah — are highlighted, along with significant dates like the beginning of Ramadan, Eid al-Fitr, Eid al-Adha, and the Day of Arafah. Each day shows both its Hijri and Gregorian date for easy cross-reference.
How Hijri Dates Are Determined
The start of each Hijri month depends on when the new crescent moon becomes visible after the astronomical new moon (conjunction). Different Islamic authorities apply different visibility criteria. The Umm al-Qura calendar, used in Saudi Arabia, relies on calculations for Mecca as a reference point. MABIMS, used across Southeast Asia, requires the moon to reach minimum altitude and elongation angles. ISNA uses astronomical calculations suitable for North America.
These differences in methodology mean that the same Hijri date may fall on different Gregorian days depending on which criterion is followed — this is why Ramadan and Eid dates can vary by 1–2 days between countries. Zaman supports multiple criteria so you can follow the convention used by your local community or Islamic authority.
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Frequently Asked Questions
What is the Hijri calendar?▾
The Hijri (Islamic) calendar is a purely lunar calendar of 12 months based on the cycles of the moon, totaling 354 or 355 days per year. It was established during the caliphate of Umar ibn al-Khattab in 638 CE, counting from the Hijra — Prophet Muhammad's ﷺ migration from Mecca to Medina in 622 CE. Because it is about 11 days shorter than the Gregorian solar calendar, Islamic dates cycle through all seasons over approximately 33 years.
What is today's Hijri date?▾
Today's Hijri date is shown at the top of this page and updates automatically each day. The exact date depends on the crescent moon visibility criterion you use — Umm al-Qura (Saudi Arabia), ISNA (North America), MABIMS (Southeast Asia), and other authorities may differ by 1–2 days. Zaman calculates the Hijri date using astronomical new moon data and your selected criterion.
What are the 12 months of the Islamic calendar?▾
The twelve Hijri months are: Muharram, Safar, Rabi al-Awwal, Rabi al-Thani, Jumada al-Ula, Jumada al-Thani, Rajab, Sha'ban, Ramadan, Shawwal, Dhul Qa'dah, and Dhul Hijjah. Four months are considered sacred (Muharram, Rajab, Dhul Qa'dah, and Dhul Hijjah). Ramadan is the month of fasting, and Dhul Hijjah is the month of the Hajj pilgrimage to Mecca.
How does the Islamic month begin?▾
Traditionally, a new Islamic month begins when the crescent moon (hilal) is sighted after sunset following a new moon (conjunction). Different authorities use different criteria: some require physical sighting with the naked eye, others accept astronomical calculations, and some use a combination. This is why Eid and Ramadan dates sometimes vary between countries and communities.
Why do Islamic dates shift every year?▾
The Hijri calendar is purely lunar, with each year being about 11 days shorter than the Gregorian solar year. This means Islamic events like Ramadan, Eid al-Fitr, and Eid al-Adha fall approximately 11 days earlier each Gregorian year, cycling through all four seasons over roughly 33 years. This ensures Muslims experience fasting and pilgrimage in every season over time.
What Islamic events are marked on the Hijri calendar?▾
Key events include: Ramadan (fasting month), Eid al-Fitr (1 Shawwal), Eid al-Adha (10 Dhul Hijjah), the Day of Arafah (9 Dhul Hijjah), Islamic New Year (1 Muharram), Ashura (10 Muharram), Mawlid an-Nabi (12 Rabi al-Awwal), Isra Mi'raj (27 Rajab), Laylat al-Qadr (odd nights in last 10 of Ramadan), and the beginning of Hajj season. Zaman marks all these events on the calendar automatically.