How are prayer times calculated, and why do apps differ by a few minutes?

Prayer times are calculated from the position of the sun relative to the horizon at your location. That requires latitude, longitude, the date and the time zone: midday is tied to the sun reaching its highest point, and the other times to the sun reaching a particular angle of elevation or depression.

Four main reasons for the difference

• The solar angle chosen for Fajr and Isha: calculation methods use different angles (18°, 19° or 15°, for example). This is why the calendars of the Kazakhstan Muftiyat, the Turkish Diyanet, the Muslim World League and Umm al-Qura differ from one another.

• The shadow ratio used for Asr: in the Hanafi calculation Asr begins when an object’s shadow reaches twice its own length; in the other views, once its own length.

• Elevation above sea level: at a high altitude the sun sets below the horizon later, which pushes Maghrib a few minutes back.

• Rounding: some calendars round the minute up as a precaution, others round it down.

Which one should you follow?

A few minutes of difference between two apps is normal. The soundest choice is to follow the official calendar of the country you are in (the Muftiyat in Kazakhstan, the Diyanet in Türkiye); in this app you can select the calculation method from the settings.