How prayer times are calculated
Prayer times shift every day because they follow the sun's actual position in the sky, not a fixed clock schedule. Fajr begins at true dawn (before sunrise), Dhuhr shortly after the sun passes its highest point, Asr in the mid-to-late afternoon, Maghrib right at sunset, and Isha once twilight has fully faded. This tool calculates all five using your device's location together with standard astronomical formulas.
Why times can differ slightly between apps
Different Islamic authorities and regions use slightly different angle conventions to define the start of Fajr and Isha (for example, some use 15°, others 18° below the horizon), which can shift those two times by a few minutes depending on the calculation method used. Dhuhr, Asr, and Maghrib are far more consistent across methods since they follow the sun's position more directly.