HOME · FAQ
Islamic Calendar FAQ
Clear, concise answers to common questions about Hijri dates, lunar months, moon sighting, Ramadan, and Islamic calendar terminology.
About Islamic dates: Hijri dates may differ by location and methodology. IslamCal labels dates as Confirmed, Calculated, Estimated, or Locally observed. Learn how dates are determined →
Use these answers as a starting point, then follow the links for full explanations and practical guidance. This hub stays focused on calendar questions rather than general Islamic topics.
Today and the current date
What is the Islamic date today?
The Hijri date changes at sunset, so the answer depends on your location and the method your community follows. See Today’s Islamic Date for IslamCal’s clearly labeled current reference.
What Islamic month is it?
Check the Today page for the current Hijri month and date, then open the linked month guide for its meaning, history, and important days.
What year is it in Islam?
Islamic years are counted from the Hijrah, the Prophet Muhammad’s ﷺ migration from Makkah to Madinah. The current year is shown on the Today page and throughout IslamCal’s calendar.
When does the Islamic day begin?
An Islamic date begins at sunset, not at midnight. This is why the Hijri date may change during a Gregorian evening.
How the calendar works
How many months are in the Hijri calendar?
There are twelve lunar months: Muharram through Dhul Hijjah. Explore all twelve in the Islamic months guide.
How many days are in an Islamic year?
A Hijri year normally has 354 days; some calculated leap years have 355. Each month has 29 or 30 days.
Why is the Islamic calendar lunar?
Its months follow the moon’s phases. The Qur’an identifies lunar crescents as markers of time, and Prophetic guidance connects Ramadan and Eid to establishing the new month.
Why does Ramadan move each year?
Because a Hijri year is about 10–11 days shorter than a Gregorian solar year, Ramadan begins roughly 10–11 days earlier each Gregorian year.
What is the difference between Hijri and Gregorian calendars?
The Hijri calendar is lunar and begins from the Hijrah; the Gregorian calendar is solar and organized around Earth’s yearly orbit. Use the date converter to compare dates.
Moon sighting and date differences
Why can Hijri dates differ by country or community?
Communities may use local or global sightings, different visibility criteria, or calculated calendars. Sunset time and authority decisions can also differ. Read How an Islamic month begins.
Is the Islamic calendar based on moon sighting or calculation?
Actual crescent sighting is foundational for ritual month beginnings in Prophetic guidance. Calculations are widely used for planning and visibility assessment, while scholars and institutions differ on whether calculation alone establishes a religious month.
How is Ramadan determined?
Ramadan begins when the new month is established by the method adopted by a recognized community or authority—commonly a valid crescent sighting, or completion of Sha‘ban as thirty days when a sighting is not established.
What is the difference between conjunction and crescent visibility?
Conjunction (ijtima‘) is the astronomical alignment associated with the new moon. The first visible crescent (hilal) appears later and depends on altitude, elongation, atmospheric conditions, and location.
Should I follow IslamCal or my local mosque?
IslamCal provides transparent calculated, estimated, confirmed, or locally observed references. For worship dates, follow the recognized authority or community you trust locally.
History, terms, and important days
Who instituted the Hijri calendar?
The formal Hijri era was instituted during the caliphate of ‘Umar ibn al-Khattab, with the year of the Hijrah chosen as its starting point.
What does AH mean?
AH abbreviates Anno Hegirae, “in the year of the Hijrah.” It labels years after the Hijrah. See the glossary for AH, BH, and other terms.
What are the four sacred months?
Muharram, Rajab, Dhul Qa‘dah, and Dhul Hijjah are the four sacred months. Learn their context in the month guides.
What are the White Days?
The White Days (Ayyam al-Bid) are the 13th, 14th, and 15th of each Hijri month. Voluntary fasting on these days is recommended; see the events guide.
What are the Days of Tashriq?
They are the 11th, 12th, and 13th of Dhul Hijjah, following Eid al-Adha. They are days of eating, drinking, and remembrance of Allah, with specific Hajj relevance.