This guide explains why prayer time apps disagree in plain language, with the exact figures and how to work them out yourself.
Last updated: August 1, 2026
Five daily prayers are anchored to solar events: Fajr at true dawn, Dhuhr just after solar noon, Asr by shadow length, Maghrib at sunset, and Isha when twilight ends. Sunset and noon are unambiguous astronomy, which is why apps rarely disagree about Dhuhr or Maghrib. The disputed frontier is twilight — exactly how far below the horizon the sun sits when “true dawn” breaks and when night fully arrives — because the Quranic descriptions describe light phenomena that scholars translated into slightly different angles.
The major conventions differ mainly in those angles. The Muslim World League uses 18° for Fajr and 17° for Isha; the University of Islamic Sciences, Karachi uses 18° and 18° (the standard across Pakistan, India, and Bangladesh); Egypt’s General Authority uses 19.5° and 17.5°; North America’s ISNA adopted 15° and 15°, yielding later dawns and earlier nights; and Saudi Arabia’s Umm al-Qura sets Fajr at 18.5° but defines Isha simply as 90 minutes after Maghrib (120 in Ramadan). One city, five defensible timetables — differing by ten to twenty-five minutes at the edges of the day.
Asr adds a second, older split. The majority (Shafi’i, Maliki, Hanbali) position begins Asr when an object’s shadow equals its height; the Hanafi school waits until the shadow doubles it, placing Asr roughly forty minutes to an hour later. Apps offering a “juristic method” toggle are asking exactly this question.
High latitudes require a third layer of judgment: in midsummer Britain or Scandinavia the sun may never reach 18° below the horizon, so no astronomical Fajr or Isha exists. Recognized solutions include using the night’s middle point, a fixed proportion of the night, or the timetable of the nearest moderate latitude — and mosque committees choose among them, which is why two mosques in one northern city can announce different Isha times in June, both correctly by their adopted rule.
The practical guidance is settled and sensible: individuals follow their local mosque or country’s official authority for congregational consistency, and travelers switch methods with geography.
The prayer panel at itsdately.com uses the Karachi 18°/18° convention and displays both Asr positions, with its method stated openly — because with prayer times, the honest answer to “which is correct?” is “correct according to which convention,” and transparency is the tradition’s own standard.
The differences are old, not digital: printed timetables disagreed the same way long before apps, and mosque committees have always chosen a convention and held it for consistency of congregation. What apps added is visibility — a traveler now sees Karachi’s table beside ISNA’s on one screen — plus settings that quietly matter, like elevation, and Ramadan-specific rules such as Umm al-Qura’s extended Isha interval.
Understanding the machinery also disarms a common worry: a twenty-minute spread between methods doesn’t mean someone is praying “wrong.” Each convention is a scholarly measurement of the same described phenomenon — the first true light, the last true glow — and the tradition’s own literature records the debate respectfully across centuries. The modern etiquette follows from it: pray with your community’s timetable, and let the astronomy panel satisfy curiosity rather than replace the mosque board.
Frequently asked questions
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Further reading: PrayTimes — prayer time calculation reference.