Why Prayer Times Differ Between Apps and Websites

You open one app and Fajr has been called; you check another site and it's twelve minutes later. Which one is wrong? Usually neither. The difference isn't a broken calculation — it's different settings feeding the same equation. This page lists five common reasons prayer times differ, ordered from largest effect to smallest.

Cause one: a different angle

Sunrise, Dhuhr and Maghrib have direct geometric definitions that nobody disputes. Fajr and Isha are tied to twilight, and twilight is a gradual fade rather than an instant. So each authority picked a threshold: how far the sun has sunk below the horizon.

When one source uses a 15° Fajr and another uses 19.5°, the gap between them in Cairo on 21 March 2026 is twenty-one minutes. Neither is wrong; each is applying its own threshold.

And that gap doesn't stay fixed. At mid-latitudes one degree is worth about five minutes in winter and can reach seven near the summer solstice. Compare in January, compare again in June, and the difference has changed — which by itself confuses a lot of people. The methods and their angles are covered in the calculation methods guide.

Cause two: the authority's minute adjustments

Some authorities don't publish the raw angle result. They publish a table with precautionary minutes added.

The clearest officially documented case is Turkey. Diyanet İşleri Başkanlığı publishes an explicit temkin table: sunrise is shifted seven minutes earlier, while five minutes are added to Dhuhr, four to Asr and seven to Maghrib; no adjustment is applied to imsak or Isha.

So if two sources compute exactly the same angle, and one applies that table while the other doesn't, sunrise will differ by seven minutes even though the astronomy is identical. This is a common source of a small, stubbornly constant offset.

Cause three: coordinates

Prayer times are computed for a point, not a city. If two sources place you at different points, the times differ.

But the size of this effect is widely overestimated. We measured Cairo on 27 August 2026 using the Egyptian method:

Across roughly thirty-two kilometres, the spread is one minute. Coordinates are not a convincing explanation for a ten-minute difference.

The large effect appears when the geographic spread widens inside a single time zone. All of Spain shares one clock in summer, yet — computed with MWL for 27 August 2026:

Forty-five minutes between the two ends of one country on one clock. If one source uses your city's coordinates and another falls back to the capital or a country centroid, that alone produces a large gap.

Cause four: time zone and daylight saving

The astronomical moment is the same; the clock it's displayed on depends on the offset. London makes this clean:

The last two rows are the same astronomical moment. The full hour between them comes purely from the offset. A difference of exactly one hour is almost always a time zone or DST issue, not a calculation one.

Cause five: rounding

Times are displayed to the minute; the calculation produces a more precise value. This site rounds to the nearest minute, while another source may simply truncate the seconds. The result can differ by a full minute on the same underlying value.

Cairo, 27 August 2026, Egyptian method:

Across thirty times over five days, the two policies disagreed on sixteen of them — about half, because the seconds exceed thirty roughly half the time. The gap is one minute and has nothing to do with astronomy: it's the policy alone.

The special case: high latitudes

The further north or south you go, the sooner you reach a day when the sun never sinks to the required angle at all. There is no astronomical Fajr or Isha that day — not because the calculation failed, but because the event didn't occur.

The three rules

A rule that divides the night between Maghrib and sunrise is used instead. The three conventional ones are:

• Middle of the night — the night is halved.
• One-seventh of the night — the night is divided into seven parts; Isha begins after the first, Fajr at the start of the last.
• Angle-based — the night is divided in proportion to the angle over sixty.

This is not a small technical detail. Stockholm (59.33°N) computed with MWL:

In May the spread exceeds two hours; by December it nearly vanishes. If you're in the north and see a huge difference between two apps, the cause is probably a different rule, not a different angle.

PrayTimes documentation labels the angle-based method as a recommended option. TimesPrayers independently uses AngleBased as its current default high-latitude rule.

A TimesPrayers-specific rule for Germany

For German locations, TimesPrayers applies its own DEHybrid rule, which first asks: does the sun actually reach the angle today, with enough margin? If it does, the real astronomical calculation is used; otherwise the estimate is.

The difference is real, not theoretical. Frankfurt on 21 May 2026 with MWL: the hybrid rule gives Fajr at 02:33 while the angle-based rule gives 03:02 — twenty-nine minutes apart. On most days of the year the two agree exactly; the divergence is confined to the late-spring and summer weeks where the question actually has an answer.

Asr is an entirely separate cause

Two sources can agree on everything above and still differ on Asr alone, because Asr has two definitions: when an object's shadow equals its length, or twice its length.

The difference isn't marginal. Cairo on 21 March 2026 with MWL: the first definition gives 15:30, the second 16:24 — fifty-four minutes. If your discrepancy is in Asr alone and is roughly that size, this is very likely the cause. This site uses shadow factor 1 by default and supports the other.

How to compare two sources fairly

Before deciding one is wrong, match all five:

1. The same date — times move daily.
2. The same coordinates — not "Cairo" in one and "central Cairo" in the other.
3. The same method — both of its angles.
4. The same Asr definition.
5. The same offset — including daylight saving.

If all five match and a minute or two remains, that's rounding. If an hour remains, it's the time zone. If two hours remain and you're in the north, it's the high-latitude rule.

And the practical rule still holds: follow what your mosque or your country's authority uses.