Fajr and Isha angles explained: 12 vs 15 vs 18 degrees
Fajr and Isha are computed from an angle of the sun below the horizon, and French timetables do not all use the same one: 12° for Musulmans de France (formerly UOIF), 15° or 18° for others, 18° (Fajr) and 17° (Isha) for the Muslim World League. The bigger the angle, the earlier Fajr and the later Isha: in Paris on 20 March, going from 12° to 18° moves Fajr 32 minutes earlier and Isha 32 minutes later in our calculations. The right angle depends on the reference your mosque follows, and opinions differ.
Updated on 20 October 2026. The times in the table are computed with the adhan library, as in the prayer times tool on this site.
Why Fajr and Isha use an angle
Dhuhr, Asr and Maghrib are computed from the position of the sun. Fajr and Isha are defined by twilight: the moment the sun has dropped a given number of degrees below the horizon, in the morning for Fajr and in the evening for Isha. In astronomy, nautical twilight is a sun between 6° and 12° below the horizon and astronomical twilight a sun between 12° and 18°. Picking 12° or 18° is therefore picking a brighter or a darker moment of the twilight. Scholars differ on which angle to retain: this guide compares calculations, it does not rule.
Angles used in France and elsewhere
| Reference | Fajr angle | Isha angle |
|---|---|---|
| Musulmans de France (formerly UOIF) | 12° | 12° |
| ISNA (North America) | 15° | 15° |
| Muslim World League | 18° | 17° |
| Karachi | 18° | 18° |
| Egypt | 19.5° | 17.5° |
| Umm al-Qura (Mecca) | 18.5° | 90 minutes after Maghrib |
What the sources we checked on 20 October 2026 say:
- The methods table of PrayTimes.org lists a "France" method (Muslims of France) at 12° for Fajr and 12° for Isha, and gives the other values above.
- Bladi.net, a widely used French site, publishes its Paris times by default with the "UOIF 12° / 12°" method and states: "Fajr est fixé à 12° sous l'horizon et Isha à 12°" (Fajr is set at 12° below the horizon and Isha at 12°).
- The blog of the association AB Argenteuil describes 12° as the "official" choice of the UOIF calendars and lists 12°, 15° and 18° as the main angles used for France.
- The Al-Kanz site states on its calendars that it does not use 12°, which it considers unsuited to Fajr in France, and offers its calendars at 15° or 18°.
- For the Grande Mosquée de Paris, we did not find an up-to-date official source on the angle. Secondary sources mention 18°; check with the mosque directly before relying on it.
What changes: Fajr and Isha at 12°, 15° and 18°
The table gives the times, in local time, computed with the same angle for Fajr and Isha. The dates are the spring equinox, the summer solstice and the winter solstice of the current year.
| City | Date | Fajr 12° | Fajr 15° | Fajr 18° | Isha 12° | Isha 15° | Isha 18° |
|---|---|---|---|---|---|---|---|
| Paris | March 20 | 05:45 | 05:26 | 05:13 | 20:12 | 20:31 | 20:44 |
| Paris | June 21 | 04:40 | 04:40 | 04:40 | 23:05 | 23:05 | 23:05 |
| Paris | December 21 | 07:23 | 07:04 | 06:45 | 18:14 | 18:33 | 18:52 |
| Lille | March 20 | 05:40 | 05:20 | 05:10 | 20:12 | 20:32 | 20:42 |
| Lille | June 21 | 04:31 | 04:31 | 04:31 | 23:09 | 23:09 | 23:09 |
| Lille | December 21 | 07:25 | 07:05 | 06:45 | 18:07 | 18:27 | 18:47 |
| Toulouse | March 20 | 05:56 | 05:39 | 05:21 | 20:09 | 20:26 | 20:43 |
| Toulouse | June 21 | 04:50 | 04:22 | 03:50 | 23:02 | 23:30 | 00:02 |
| Toulouse | December 21 | 07:15 | 06:58 | 06:40 | 18:29 | 18:47 | 19:04 |
| Marseille | March 20 | 05:40 | 05:23 | 05:06 | 19:53 | 20:10 | 20:27 |
| Marseille | June 21 | 04:36 | 04:09 | 03:38 | 22:45 | 23:11 | 23:43 |
| Marseille | December 21 | 06:59 | 06:41 | 06:24 | 18:14 | 18:32 | 18:49 |
Reading it: in Paris, the gap between 12° and 18° is 32 minutes on Fajr and 32 minutes on Isha on 20 March, and 38 minutes on Fajr and 38 minutes on Isha on 21 December. On 21 June, in Paris and Lille, the three angles give the same time: see below. Further south, in Toulouse and Marseille, the gap stays visible in summer, up to about an hour on Isha in Toulouse.
Why summer is a special case
The further north you are and the closer to the summer solstice, the less the sun drops below the horizon at night. Around 21 June, in Paris and further north, it does not reach 18° below the horizon: twilight never really ends. The calculations then need a high latitude rule. The adhan library applies the recommended rule here (one seventh of the night above 48° of latitude, the middle of the night below) as a ceiling: Fajr cannot fall earlier than one seventh of the night before sunrise, nor Isha later than one seventh of the night after sunset. In Paris and Lille on 21 June, that ceiling applies to all three angles, hence the identical times in the table. It also trims the 18° times by a few minutes in Paris and Lille around the spring equinox, which is why the gap between 15° and 18° looks smaller there than the gap between 12° and 15°. Mosque timetables and apps do not all apply the same rule, which partly explains why two sources can show times far apart in summer. High latitude rules are also debated.
How to choose your angle
- Look at your mosque's timetable: it is the simplest reference, and the one most worshippers who pray there follow.
- If you follow a specific school or scholar, see which angle its timetable uses.
- Set your tool or app to the same method, then compare a few days to check that the times match to the minute. Keep in mind that the mosque sometimes shows the iqama time, a few minutes after the adhan.
In the free prayer times tool, the method is chosen from a list (12° Musulmans de France, 18° and 17° Muslim World League, 15° ISNA and others). Each city page, for example Paris, compares the three angles for the day. In the QuranWay app, the calculation method is set in the settings and the method in use is shown on the Prayer screen.
Sources
- PrayTimes.org, calculation methods table: https://praytimes.org/docs/methods
- Bladi.net, prayer times in Paris (default method UOIF 12° / 12°): https://www.bladi.net/horaires-priere/france/paris.html
- AB Argenteuil, "Les horaires de prière et la Ligue islamique mondiale" (12°, 15° and 18° angles in France): https://abargenteuil.fr/blog/ligue-islamique-mondiale-horaire-priere/
- Al-Kanz, prayer calendars (15° and 18° angles): https://www.al-kanz.org
- adhan library (Batoul Apps), high latitude rules: https://github.com/batoulapps/adhan-js