Islamic Calendar Calculator
Convert between Gregorian and Islamic (Hijri) calendar dates. View Islamic months and important holidays.
Islamic Months
July 18, 2026
2 Safar 1448 AH
Date Details
Islamic Year: 1448 AH
Month: Safar (2/12)
Day: 2
Upcoming Islamic Holidays
Prophet Birthday (Sunni)
Night Journey
Night of Fortune
Start of Fasting
Night of Power
What Is the Islamic Calendar?
The Islamic calendar (also called the Hijri calendar, or at-taqwīm al-hijrī) is a purely lunar calendar consisting of 12 months totaling 354 or 355 days per year — about 11 days shorter than the Gregorian solar year. Because it does not add intercalary months to realign with the solar year (unlike the Hebrew or Ethiopian calendars), the Islamic calendar drifts through all four seasons over approximately 32.5 years.
The Islamic calendar's epoch is the Hijra — the migration of the Prophet Muhammad from Mecca to Medina — which occurred in 622 CE. Year 1 AH (Anno Hegirae) began on Friday, July 16, 622 CE (Julian calendar). The calendar has 12 named months, each starting with the sighting of the crescent moon (hilal). For civil and computational purposes, a tabular Islamic calendar is used that assigns alternating months of 30 and 29 days according to a fixed 30-year cycle containing 11 leap years.
The Islamic year is entirely lunar, which means Islamic holidays (Ramadan, Eid al-Fitr, Eid al-Adha) advance about 11 days earlier each Gregorian year. This shift means Ramadan eventually falls in every season — a complete cycle takes about 32–33 Gregorian years.
Gregorian to Islamic Conversion
The conversion uses the Islamic (tabular) epoch as the reference point. The Julian Day Number serves as an intermediate step.
Islamic Calendar Conversion (Tabular)
Where:
- islamicEpoch= Julian Day 1948439.5 = July 16, 622 CE (Julian), the start of the Islamic calendar
- k= floor((JD − islamicEpoch) / 10631) × 30 — complete 30-year cycles elapsed × 30 years
- j= Remaining days after removing complete 30-year cycles
- i= Index of the year within the current 30-year cycle (determined by accumulating year lengths)
- yearLength= 355 days for leap years (years 2,5,7,10,13,16,18,21,24,26,29 of each 30-year cycle), 354 for regular years
The 12 Months of the Islamic Calendar
| # | Month Name | Days | Notable Events |
|---|---|---|---|
| 1 | Muharram | 30 | Islamic New Year (1 Muharram), Ashura (10 Muharram) |
| 3 | Rabi al-Awwal | 30 | Mawlid al-Nabi (Prophet's Birthday, 12th) |
| 7 | Rajab | 30 | Laylat al-Miraj (27 Rajab) |
| 9 | Ramadan | 30 | Month of fasting; Laylat al-Qadr (27th) |
| 10 | Shawwal | 29 | Eid al-Fitr (1 Shawwal) |
| 12 | Dhu al-Hijjah | 29/30 | Hajj pilgrimage; Eid al-Adha (10th) |
How to Use This Calculator
- Select a Gregorian Date: Use the date picker to choose the date you want to convert. The calculator defaults to today's date.
- View the Islamic Date: The converted Hijri date displays in the format Day Month Year AH (e.g., 15 Ramadan 1446).
- Check the Month List: The twelve Islamic months are listed, with the current month highlighted for quick orientation.
- Review Holidays: The holidays panel lists major Islamic observances referenced to specific Islamic calendar dates.
Important note: This calculator uses the tabular Islamic calendar (a computational approximation). Actual Islamic months in practice begin with the visual sighting of the crescent moon, which may differ by 1–2 days from the tabular date depending on location and observing conditions.
Real-World Applications
The Islamic calendar is the official calendar in Saudi Arabia, Iran (alongside the Solar Hijri), and several other predominantly Muslim countries. Knowledge of the Hijri calendar is essential for understanding Islamic finance (where contracts may reference Hijri dates), halal food certification timelines, and international business with partners in the Gulf Cooperation Council (GCC) countries.
Ramadan — the ninth month — is the most widely observed Islamic period, during which approximately 1.8 billion Muslims fast from dawn to sunset. Businesses serving Muslim customers or employing Muslim staff in significant numbers plan reduced working hours, adjusted delivery schedules, and special product offerings for Ramadan. The Hijri date converter helps identify exactly when Ramadan begins each Gregorian year.
Genealogists researching Muslim families in historical records from the Ottoman Empire, Mughal India, or other Islamic civilizations often encounter dates given in AH notation. Converting these to Gregorian dates requires the Hijri-to-Gregorian conversion that this calculator provides in reverse.
Worked Examples
Convert June 7, 2026 to Hijri
Problem:
What is June 7, 2026 in the Islamic (Hijri) calendar?
Solution Steps:
- 1Compute Julian Day for June 7, 2026: JD ≈ 2461218.5
- 2Islamic epoch JD = 1948439.5
- 3Days since epoch = 2461218.5 − 1948439.5 = 512,779 days
- 4Complete 30-year cycles: floor(512779 / 10631) = 48 cycles = 48 × 30 = 1440 years
- 5Remaining days: 512779 − 48 × 10631 = 512779 − 510288 = 2491 days
- 6Count through year lengths to find year within cycle and remaining days for month/day
Result:
June 7, 2026 ≈ approximately 12 Dhu al-Hijjah 1447 AH (exact date may vary by 1 day due to moon sighting).
When Does Ramadan Begin?
Problem:
How do I find when Ramadan begins in a given Gregorian year?
Solution Steps:
- 1Ramadan begins on 1 Ramadan (9th month of the Hijri year)
- 2Because the Islamic year is ~11 days shorter than the Gregorian year, Ramadan shifts earlier each year
- 3For example: Ramadan 2024 began March 10–11; Ramadan 2025 began around March 1; Ramadan 2026 began around February 18
- 4Use this calculator: enter March 1 of the target year and check if the Islamic month shown is Ramadan or find the date where the month changes to Ramadan
Result:
Ramadan shifts approximately 11 days earlier each Gregorian year, completing a full cycle through all seasons in ~32.5 years.
Islamic New Year 1447 AH
Problem:
When does Islamic New Year 1447 AH fall?
Solution Steps:
- 1Islamic New Year = 1 Muharram of the target Hijri year
- 21447 AH begins approximately July 2026 Gregorian (the exact date depends on moon sighting)
- 3Tabular calculation: 1446 complete years × ~354.37 days/year + epoch gives the Julian Day, converted to Gregorian
Result:
Islamic New Year 1447 AH falls approximately in late June to early July 2026 (exact date subject to moon sighting).
Tips & Best Practices
- ✓The Islamic year shifts ~11 days earlier each Gregorian year — add 11 to find the approximate Gregorian date of the same Islamic date the following year.
- ✓Ramadan fasting hours are longer in summer (Northern Hemisphere) and shorter in winter — this varies dramatically over the 32-year cycle.
- ✓Eid al-Fitr (1 Shawwal) and Eid al-Adha (10 Dhu al-Hijjah) are the two most important Islamic holidays — plan business closures and delivery schedules around them.
- ✓The tabular calendar used here may differ by 1–2 days from the actual observed Islamic calendar in your region.
- ✓In Saudi Arabia and the Gulf states, business hours during Ramadan shift dramatically — offices often open later and close earlier.
- ✓Historical documents from the Ottoman Empire use the Rumi calendar (a solar calendar with Hijri year count) — this is different from the purely lunar Hijri calendar used here.
Frequently Asked Questions
Sources & References
Last updated: 2026-06-06
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Editorial Note
MyCalcBuddy Editorial Team
This page is maintained as an educational calculator reference.
Formula Source: Standard Mathematical References
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