How these times are calculated
Prayer times follow the position of the sun. Fajr begins when the sky starts to lighten before sunrise, measured as the sun's angle below the horizon. Dhuhr begins just after the sun passes its highest point. Asr begins when an object's shadow reaches a set length — once its height plus its noon shadow in the standard view, or twice in the Hanafi view, which is why Hanafi Asr is later. Maghrib begins at sunset, and Isha begins when the evening twilight has gone.
Why methods give different times
Organisations use different sun angles for Fajr and Isha. The Muslim World League uses 18° and 17°, ISNA uses 15° for both, and Umm al-Qura sets Isha at a fixed 90 minutes after Maghrib. Choose the method your local mosque follows; where you are unsure, the Muslim World League is a widely used default.
High latitudes
In places far from the equator, twilight may never fully end in summer. For locations above 48° latitude this tool applies a recognised adjustment so Fajr and Isha stay practical. Always confirm with your local mosque timetable, which may also add a few minutes of caution.
Want reminders and times on your phone? Salah Companion: Prayer Times is our free Android app built on the same calculations.