Hijri Calendar Explained: Umm al-Qura, Tabular and Moon Sighting

Why websites disagree

Search for today’s Hijri date and you will find sites that disagree. One says the 7th, another the 6th, and a third gives yet another answer for the start of Ramadan. None of them is necessarily wrong. They are answering slightly different questions. This guide explains the three methods behind almost every Hijri date, shows the differences with real numbers for 1448 AH, and ends with a practical way to line a converter up with your local announcement.

What the Hijri calendar is

The Hijri calendar counts twelve lunar months. A lunar month is the time from one new crescent to the next, about 29.5 days, so months last 29 or 30 days and a Hijri year lasts 354 or 355 days. A Gregorian year is 365 or 366 days, which means Hijri dates move roughly eleven days earlier against the Gregorian calendar each year. After about 33 years a given Hijri date has travelled once around the Gregorian seasons.

Years are counted from the Hijra in 622 CE and written “AH”. The twelve months in order are Muharram, Safar, Rabi al-Awwal, Rabi al-Thani, Jumada al-Awwal, Jumada al-Thani, Rajab, Shaban, Ramadan, Shawwal, Dhu al-Qadah and Dhu al-Hijjah.

Method 1: Umm al-Qura

Umm al-Qura is a calculated calendar. Its month lengths are fixed in advance from astronomical criteria, so a date can be looked up years ahead. It is the calendar Saudi Arabia uses for civil and administrative purposes, and it is the one built into the international date data that modern browsers ship. The converter reads it from that data for the years 1300 to 1600 AH.

Because it is calculated, Umm al-Qura is predictable, which is why calendar apps and spreadsheets like it. Its limitation is that it is a calendar of dates, not an announcement that the crescent has been seen in your country.

Method 2: the tabular civil calendar

The tabular civil calendar ignores the moon altogether. It repeats a 30-year cycle in which odd-numbered months have 30 days, even-numbered months have 29 days, and eleven years in every thirty add one day to Dhu al-Hijjah. It can be computed for any year with arithmetic, which makes it useful as a fallback, but the moon does not follow a fixed pattern, so the tabular calendar can sit a day or two away from Umm al-Qura or from what is observed.

To measure the difference, the first day of every month was compared under the two calendars for the sixteen years 1445 to 1460 AH, which is 192 months. In 80 of those 192 months the first day of the month differs between Umm al-Qura and the tabular civil calendar. The difference is always small, but it is frequent, so a converter should say which calendar it uses.

Method 3: local moon sighting

Many countries and communities start a Hijri month only after an official announcement that the new crescent has been sighted. The announcement is made on the evening of the 29th. If the crescent is seen, the new month begins the next day; if not, the current month completes 30 days. Because sighting depends on the weather and on where observers stand, the announced date can be a day later than a calculation, and different countries can announce different days.

This is the source of most day-of-the-month disagreements between a calculated calendar and local practice.

A worked example for 18 October 2026

On 18 October 2026, UrduPoint listed the date as 7 Jumada al-Awwal 1448 for Saudi Arabia, using Umm al-Qura, and 6 Jumada al-Awwal 1448 for Pakistan, citing the Central Ruet-e-Hilal Committee. Here is the same day under each setting in the converter:

The offset setting exists for exactly this situation: it shifts the lookup by up to two days so the converter matches the date announced where you live.

When do the months of 1448 AH start?

Under Umm al-Qura with no offset, the first day of each month of 1448 AH falls on these dates. The tabular civil start is shown for comparison. These are calculated dates, and local sighting can move any of them by a day.

For Ramadan 1448, several sources agree on Monday 8 February 2027 as the expected first day under calculation. AlAdhan’s Ramadan calendar lists 1 Ramadan 1448 on 8 February 2027, and IslamicFinder lists Ramadan 2027 starting on 8 February and Eid al-Fitr on 9 March. Where a community begins the month a day later, the dates move to 9 February and 10 March.

Does the Hijri day begin at sunset?

In the Islamic reckoning each day runs from sunset to sunset, not from midnight to midnight. That is why the evening before a date can already carry the new Hijri date. A converter that follows the Gregorian midnight rule will show the older date until midnight. The Hijri date converter has an “after sunset” box that adds one day to the Hijri result for that reason.

How to line a converter up with your local date

1. Find today’s Hijri date from the announcement your community follows.
2. In the converter, open “Match my local date” and enter that day, month and year.
3. The tool works out the offset needed so that today shows that date. An offset of −1 means your local date is one day behind the basis.
4. Re-check at the start of each month. A single offset is an approximation, because a community can be a day behind one month and level with the basis the next.

Putting dates into your calendar

Once the offset matches your local practice, the Islamic dates tab can export Ramadan, Eid, Arafah, the Islamic New Year and Ashura as an .ics calendar file for up to five years at a time. Every event states the basis and offset used, and you can add a reminder for the day before. The My Hijri date tab does the same for a Hijri birthday or anniversary. Remember that a calendar file holds calculated dates; when the real announcement differs by a day, trust the announcement and adjust the entry.

Common questions

Sources

Reviewed on 19 Oct 2026 against the published sources below. Laws and prices change, so check the current position before you rely on a figure.

• AlAdhan: Islamic Calendar API, which describes its calendar as built on the Umm al-Qura method, and the AlAdhan Ramadan calendar for 2027
• UrduPoint: Islamic date today worldwide, for the 18 October 2026 Saudi Arabia and Pakistan dates
• IslamicFinder: Islamic date converter and Ramadan calendar, for the 8 February and 9 March 2027 dates
• Unicode ICU calendar data as exposed by the browser Intl API (islamic-umalqura, islamic-civil), for the calculations in the tables

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