Why Prayer Apps Show Different Fajr and Isha Times

If your app says Fajr is at 4:12 and your masjid's timetable says 4:35, neither is necessarily wrong. Every prayer app turns the position of the sun into clock times using a small set of published parameters — its prayer time calculation method. Dhuhr and Maghrib hardly vary between methods, because solar noon and sunset are fixed astronomical moments. Fajr and Isha depend on how dark the sky has to be, and different bodies answer that with different angles. Asr depends on your school of fiqh. Change any of these settings and the times move.

Below: each setting in plain language, the common methods side by side, and how to set things up in Aydeen. We don't argue that one method is correct; scholars and national bodies differ.

Why two apps disagree

Each prayer is tied to the sun: Dhuhr just after solar noon, Asr when shadows reach a set length, Maghrib at sunset, Fajr at true dawn and Isha once twilight has gone. Noon and sunset are single moments. Dawn and dusk are gradual, so each method has to choose a threshold.

Disagreements usually come from:

• Twilight angles for Fajr and Isha: the biggest cause.
• Asr convention: Standard or Hanafi.
• A high-latitude rule taking over in summer.
• Location: a city centre, an old GPS fix or the wrong time zone.
• Timetable conventions: many masjids print the iqamah time, when the congregation stands, and some add precautionary minutes.

Prayer time calculation methods compared: the Fajr and Isha angles

A method mostly boils down to two angles: how many degrees the sun sits below the horizon at Fajr and at Isha. A bigger angle means a darker sky, so Fajr comes earlier and Isha later.

We ran the numbers with adhan, the open-source library Aydeen uses. In Chicago on 10 September 2026, ISNA (15°) puts Fajr at 5:07 a.m., the Muslim World League (18°) at 4:49 a.m. and the Egyptian method (19.5°) at 4:41 a.m. Isha runs the other way: 8:27 p.m. with ISNA, 8:38 p.m. with the Muslim World League and 8:44 p.m. with Karachi's 18°. The gaps vary with latitude and season.

The sun is the same for everyone. What differs is where each method draws the line.

Angles as published by the adhan library and PrayTimes.org. The Moonsighting Committee and Diyanet rows come from adhan, which calls its Diyanet settings an approximation, and the JAKIM row from AlAdhan's method list. Official timetables may add their own precautionary minutes, so a body's own published timetable is always the reference.

You'll often see this debated as "Fajr angle 18 vs 15". The Fiqh Council of North America, for example, suggests 15° for both Fajr and Isha in the USA and 13° in Canada, while other bodies use 18° or more. We list these positions side by side, not in order of merit.

Asr: shadow length, Standard vs Hanafi

Asr is measured with shadows. At solar noon an upright object casts its shortest shadow, which then lengthens through the afternoon. The conventions differ on how long it must get:

• Standard (the Shafi'i, Maliki and Hanbali position): Asr begins when an object's shadow equals its own height, plus the length of its noon shadow.
• Hanafi: Asr begins when the shadow reaches twice the object's height, plus the noon shadow.

So Hanafi Asr always comes later. In Karachi on 10 September 2026, Standard Asr begins at 3:57 p.m. and Hanafi Asr at 4:57 p.m. In Chicago the same day it's 4:21 p.m. and 5:16 p.m. Only Asr changes; the other four times stay put.

The difference is an old one. As an answer on SeekersGuidance explains, Imam Abu Hanifa held the two-shadow position, while his students Abu Yusuf and Muhammad ibn al-Hasan held the one-shadow position.

High-latitude summers: three common rules

Twilight angles assume the sun sinks far enough below the horizon each night. Further from the equator, around midsummer, it doesn't. In London on 21 June the sun gets no more than about 15° below the horizon, so an 18° Fajr or a 17° Isha never technically arrives. Places further north, such as Scotland and Scandinavia, face the same problem for longer.

Apps handle this with a high-latitude rule, which limits how early Fajr and how late Isha can be:

In the adhan library the rule is a limit: the angle-based time is used unless it never arrives or falls beyond the limit. The choice matters. For London on 21 June 2026 with the Muslim World League angles, Fajr comes out at 1:02 a.m. under Middle of the night, 2:31 a.m. under Twilight angle and 3:40 a.m. under One-seventh. Isha comes out at 1:02 a.m., 11:27 p.m. and 10:25 p.m. respectively.

If your local masjid publishes a summer timetable, follow that.

How to choose: match your local masjid

We don't rank the methods. For daily life, the practical approach is to use what your local masjid uses, so your adhan and the congregation line up.

• Find your masjid's timetableWebsite, noticeboard or printed sheet. Many name the method or the angles in the small print.
• Separate start times from iqamah timesCompare your app with the time each prayer begins, not with when the jama'ah stands.
• Pick the matching method and Asr conventionIf the timetable doesn't say, ask the imam or the masjid committee.
• Compare a few daysConsistently a few minutes out? The timetable may add precautionary minutes; a per-prayer adjustment closes the gap.
• Travelling?Set your location to where you are and look up a local masjid's timetable there.

If your trip is for Umrah, our Umrah packing list and our guide to keeping count in Tawaf and Sa'i cover the rest of the journey.

Setting it up in Aydeen

Aydeen's prayer settings follow the same approach: choose the method your masjid uses, then fine-tune. In Prayer settings you'll find:

Prayer times and the adhan are among Aydeen's always-free features. The free tier shows non-personalised, G-rated banner ads, which Premium removes. For the rest of the daily features, see our tour of Aydeen's daily worship features.

Frequently asked questions

Is there a method or a local timetable Aydeen doesn't match yet? Email hello@aydeen.com — we read everything.