Why Prayer Times Differ Between Apps (and Which Method to Choose)

If you have ever compared two prayer apps and found Fajr differing by half an hour, nothing is broken — they are using different calculation methods. Understanding why removes the confusion and helps you choose the setting that matches your local mosque.

What is actually calculated

Dhuhr, Asr, Maghrib and sunrise are pure astronomy — the sun's position at your coordinates — so they barely differ between apps. Fajr and Isha, however, depend on twilight: Fajr begins when true dawn appears and Isha when twilight disappears. How far below the horizon the sun must be for that (the 'twilight angle') is where methods disagree.

The major methods

• Muslim World League (MWL): Fajr 18°, Isha 17° — a widely used international default (and Noor's default).
• ISNA (North America): Fajr 15°, Isha 15° — later Fajr, earlier Isha; common in the US and Canada.
• Umm al-Qura (Saudi Arabia): Fajr 18.5°, Isha fixed at 90 minutes after Maghrib — used in the Gulf.
• Egyptian General Authority: Fajr 19.5°, Isha 17.5° — common in Egypt, Africa and parts of Asia.
• University of Karachi: Fajr 18°, Isha 18° — common in Pakistan, India and Bangladesh.

The Asr question: standard or Hanafi?

Asr has its own difference: the standard (Shafi'i/Maliki/Hanbali) position begins Asr when an object's shadow equals its length; the Hanafi position waits until the shadow is twice the length, making Asr roughly 45–60 minutes later. Noor lets you toggle Hanafi Asr on the prayer times page.

Which should you choose?

• Follow your local mosque or country's religious authority — congregation unity comes first.
• If unsure, use your region's conventional method (ISNA in North America, MWL in Europe, Umm al-Qura in the Gulf, Karachi in South Asia).
• At high latitudes (Northern Europe in summer), twilight may never end; apps then use special rules — ask your local mosque which convention it follows.

Noor supports all the major methods with the Hanafi Asr option, for 600+ cities worldwide — free and ad-free at noor.style/prayer-times.