If prayer calendars differ, which is to be relied on for prayer

Question

Between the “Dawami Islamic Jantri” (“The Perpetual Islamic Calendar”) and the “Qasimi Jantri” (“The Qasimi Calendar”) there is a difference of approximately 4 minutes. The calendar has been prepared according to radio time: on the first page of the “Qasimi Jantri” a note states that those using this calendar should keep their clocks set to radio time.

Answer

A difference of four minutes is not such that observing it would cause any hardship. The prayer should be performed precisely with it taken into account, so that the prayer is valid according to both [calendars].

Source: Fatawa Mahmudiyya

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