Calculation Methodology & Data Sources
Hijri calendar
The site uses the official Umm al-Qura calendar (issued by Umm al-Qura University in Makkah and published at ummulqura.org.sa) for Hijri–Gregorian conversion over 1300–1500 AH (approximately 1882–2077 CE). Every month table is built from the official month starts in this calendar.
The ±1 day sighting adjustment
An Islamic month begins with the sighting of the new moon or the completion of 30 days, which can differ by one day between countries depending on sighting and the official announcement. For this reason every date page provides an adjustment switch (one day earlier / one day later) to match your country’s official announcement.
Prayer times calculation
Prayer times are computed from the sun’s position (declination and equation of time) for each individual day. Fajr and Imsak use the twilight angle of the chosen method; Sunrise and Maghrib occur when the center of the sun is 0.833° below the horizon (refraction and solar radius corrected); Dhuhr is the transit of the sun across the local meridian; Asr follows shadow length according to the selected school (majority or Hanafi).
Supported calculation methods
Umm al-Qura (Saudi Arabia; Isha 90 minutes after Maghrib), Muslim World League (18/17 degrees), ISNA for North America (15/15), Egyptian General Authority of Survey (19.5/17.5), University of Islamic Sciences Karachi (18/18), and others. Each country defaults to its convention, and the method can be changed.
Local time
All times are shown in the city’s local time using the IANA time zone database, accounting for daylight saving on a per-date basis.
Qibla direction
Qibla bearing is calculated as the great-circle path from your city’s coordinates to the Kaaba, with distance measured along the earth’s surface.
Moon phase
The moon phase tool reports lunar age and illumination from the mean synodic month (about 29.53 days) using an approximate astronomical algorithm with an error margin of roughly half a day — sufficient for general display purposes. The start of Hijri months, however, is taken exclusively from the official Umm al-Qura calendar, never from the moon phase computation.
City coordinates
City coordinates come unmodified from the open GeoNames database (CC BY 4.0), with Arabic names matched from the alternate-names records of the same database.
Accuracy verification
We regularly cross-check our results against independent sources: prayer times typically match published timetables of major cities within one minute, and any observed deviation is corrected promptly. If you spot a discrepancy for your city, let us know via the contact page.