Every year the same question arrives in the last ten days: my family abroad is observing the 27th night tonight and our mosque is observing it tomorrow — which one is right?
Both are, in the only sense the question can be answered. The night is identified by a count of days within Ramadan, and communities do not agree on the day Ramadan began. A disagreement at the start propagates all the way to the end.
Where the disagreement comes from
The Islamic month begins with the new crescent, and there are two broad approaches to determining it: sighting the crescent with the eye, and computing whether it is astronomically visible. Different countries follow different approaches, and some that sight locally will accept a sighting from elsewhere while others will not.
The result is routinely a one-day and occasionally a two-day spread in when Ramadan starts. We went through the mechanics of that in why Ramadan and Eid start on different days, and it is the whole of the explanation here — if your Ramadan began on a Tuesday and your cousin's on a Wednesday, your 27th night is her 26th, arithmetically and unavoidably.
There is a second, smaller source of confusion. The Islamic day begins at sunset, so the night of the 27th is the night that precedes the daytime of the 27th, not the one that follows it. People counting forward from a daytime date land a night late. This trips up far more people than the sighting dispute does.
What is actually specified
The revelation is emphatic about the night's value and reticent about its date, and the reticence appears to be deliberate.
Surah al-Qadr describes it as better than a thousand months — you can read the surah at Al-Qadr. The reported guidance directs seeking it in the last ten nights, and more particularly in the odd-numbered ones. A widely transmitted report has it that the Prophet was about to disclose the exact night when a dispute between two men caused the knowledge to be withdrawn, and he said that this might be better for the community.
The 27th has the strongest support among the specific candidates and a number of companions held that view firmly, but the classical literature records a range of opinions across the odd nights, and several scholars concluded that the night moves from year to year. That is a genuinely unsettled question in the tradition rather than a modern uncertainty.
The practical consequence of not knowing
If the exact night were known, the rational response would be to concentrate everything on it. Because it is not, the instruction effectively becomes to treat all of the last ten nights as candidates — which is very plausibly the point.
This is also why the calendar disagreement matters less than it first appears. A community observing the odd nights across a range is going to include the night whichever reckoning is correct, and a person who marks only one night on a calendar that turns out to be a day off has missed it regardless of how confident they were.
The established practice built around this is i'tikaf — remaining in the mosque for the last ten days — which is precisely a strategy for not needing to know the date. The same logic explains why mosques schedule extended night prayers across all ten rather than one.
What to do if the dates around you disagree
Follow the calendar your local community follows. This is the standard advice and it is not a fudge: praying and breaking fast with the people around you is itself weighted in the tradition, and a household running on a different calendar from its mosque creates more difficulty than the precision is worth.
If you want to cover the disagreement, observe the odd nights on your local reckoning and add the adjacent nights — a one-day spread is covered by treating both the 26th and 27th as candidates, which costs one extra night.
The table shows how the offset propagates. Two communities whose Ramadan began a day apart never converge: every numbered night stays one evening out, right through to Eid.
| Night | Ramadan began Monday | Ramadan began Tuesday |
|---|---|---|
| 21st | Saturday evening | Sunday evening |
| 23rd | Monday evening | Tuesday evening |
| 25th | Wednesday evening | Thursday evening |
| 27th | Friday evening | Saturday evening |
| 29th | Sunday evening | Monday evening |
Working the dates out yourself
If you want to mark the candidate nights in a calendar, our Islamic calendar page lays out the dates for the coming years. One caveat applies to that page and to every printed Hijri date anywhere: it is a calculated calendar, and it may differ by a day from a locally sighted month — a point we went into in why your phone's Hijri date doesn't match.
The safe way to use any printed date for the last ten nights is as an anchor rather than an answer. Find the 21st on the calendar, confirm it against what your mosque announces once Ramadan has actually begun, and adjust the whole set by a day if they disagree. Because the offset is constant, a single correction at the start of the month fixes every night that follows.
And the practical question of how long that month's fast will be, which varies far more than most people expect, is measured in the twenty-hour fast is not coming back until 2047.
Common questions
- Which night is Laylat al-Qadr?
- It is not fixed by name in the sources. The guidance is to seek it in the odd nights of the last ten of Ramadan, with the 27th the most commonly cited candidate. Several scholars held that it moves from year to year, and a well-known report has the exact night deliberately left undisclosed.
- Why is the 27th night on a different date in different countries?
- Because Ramadan itself started on different days. Countries differ on sighting versus calculation for the new crescent, producing a one- or two-day spread, and that offset carries through to every numbered night of the month.
- Is the night of the 27th before or after the day of the 27th?
- Before. The Islamic day begins at sunset, so the night of the 27th is the evening preceding the daytime of the 27th. Counting forward from the daytime date puts people a night late.
- Which calendar should I follow if my family abroad disagrees?
- The one your local community follows — praying and fasting with the people around you carries its own weight, and a household out of step with its mosque creates practical difficulty. To cover a one-day spread, treat the adjacent night as a candidate too.