Calculation methods

Muslimtify derives prayer times from your coordinates, date, and timezone using established astronomical algorithms, entirely on your machine. A calculation method is the set of parameters a religious authority uses to define the edges of each prayer window, mainly the twilight angles for Fajr and Isha.

Set your method with muslimtify method, the default is kemenag.

How a method is defined

Each built-in method sets a handful of parameters:

• Fajr / Isha angle: how far the sun sits below the horizon (in degrees) at the start of Fajr and the start of Isha. A larger angle means an earlier Fajr and a later Isha.
• Isha interval: some authorities (Umm al-Qura, Qatar, Gulf, Portugal) define Isha as a fixed number of minutes after Maghrib instead of an angle.
• Maghrib offset: a small number of minutes added after sunset. Only Portugal and the Moonsighting Committee use one (3 minutes).
• Ihtiyat: a precautionary margin added to every prayer time. Only Kemenag (+2 min) and Jordan (+5 min) apply one, every other method uses 0. Sunrise gets the same margin subtracted rather than added.

The Asr time is not part of the method. It is controlled separately by your madzhab and applies identically across every method, see Asr and madzhab.

Method parameters

All angles are in degrees. "Isha interval" is minutes after Maghrib, used when the method is not angle-based. "Ihtiyat" is the precautionary margin added to each prayer (and subtracted from sunrise).

Key	Organization	Fajr	Isha angle	Isha interval	Maghrib offset	Ihtiyat
mwl	Muslim World League	18.0	17.0	—	0	0
makkah	Umm al-Qura, Makkah	18.5	—	90 min	0	0
isna	ISNA (North America)	15.0	15.0	—	0	0
egypt	Egyptian General Authority	19.5	17.5	—	0	0
karachi	Univ. of Islamic Sciences, Karachi	18.0	18.0	—	0	0
turkey	Diyanet, Turkey	18.0	17.0	—	0	0
singapore	MUIS, Singapore	20.0	18.0	—	0	0
jakim	JAKIM, Malaysia	20.0	18.0	—	0	0
kemenag	Kemenag, Indonesia (default)	20.0	18.0	—	0	+2 (−2 sunrise)
france	UOIF, France	12.0	12.0	—	0	0
russia	Spiritual Administration, Russia	16.0	15.0	—	0	0
dubai	GAIAE, Dubai	18.2	18.2	—	0	0
qatar	Ministry of Awqaf, Qatar	18.0	—	90 min	0	0
kuwait	Ministry of Awqaf, Kuwait	18.0	17.5	—	0	0
jordan	Ministry of Awqaf, Jordan	18.0	18.0	—	0	+5 (−5 sunrise)
gulf	Gulf Region (general)	19.5	—	90 min	0	0
tunisia	Ministry of Religious Affairs	18.0	18.0	—	0	0
algeria	Ministry of Religious Affairs	18.0	17.0	—	0	0
morocco	Ministry of Habous, Morocco	19.0	17.0	—	0	0
portugal	Comunidade Islamica de Lisboa	18.0	—	77 min	3 min	0
moonsighting	Moonsighting Committee	18.0	18.0	—	3 min	0

All computed times are rounded up to the next whole minute (the Kemenag convention), for every method.

Simplifications to be aware of

Muslimtify implements each method from its core angle/interval parameters. A few authorities apply extra, calendar- or location-specific adjustments in their official schedules that Muslimtify intentionally does not replicate:

• Umm al-Qura (makkah): Isha is a fixed 90 minutes after Maghrib all year. The official Saudi calendar switches to 120 minutes during Ramadan and advances the printed times by ~3 minutes, Muslimtify does neither.
• Diyanet (turkey): the official Turkish times apply a temkin correction (about 10 minutes for Istanbul). Muslimtify does not apply temkin, so its times may differ from official Diyanet schedules by that amount.
• Dubai (dubai): Muslimtify uses the plain 18.2°/18.2° angles. The small per-prayer rounding offsets seen in some official UAE tables are not applied.
• Moonsighting (moonsighting): Muslimtify treats this as a fixed 18° baseline angle plus a 3-minute Maghrib offset. The committee's real method uses seasonal, latitude-dependent curve-fit functions and multiple shafaq modes, those are not implemented.
• Morocco (morocco): official times are adjusted manually per city by the Ministry of Habous. Muslimtify approximates with the 19.0°/17.0° angles only.

Where these differences matter for your local mosque, use the per-prayer offset to line the times up exactly.

Notable per-method details (as implemented)

• Kemenag (kemenag, default): applies an ihtiyat precaution of +2 minutes to every prayer (and −2 minutes to sunrise). See Kemenag, the default.
• Jordan (jordan): applies a +5 minute ihtiyat to every prayer (and −5 minutes to sunrise). This is a whole-schedule margin, not a Maghrib-only offset.
• Portugal (portugal): Isha is a fixed 77-minute interval after Maghrib, and Maghrib itself is set 3 minutes after sunset.
• Moonsighting (moonsighting): Maghrib is set 3 minutes after sunset, Fajr and Isha use the 18° angle.

Dhuha

Muslimtify also computes a Dhuha time (sun altitude 4.3°, about 4°18′, above the eastern horizon) for every method, though it is disabled by default. Enable it with muslimtify notification enable dhuha.

Asr and madzhab

The madzhab you choose affects only the Asr calculation, through the shadow factor n. It is applied the same way regardless of which calculation method is active.

Madzhab	Shadow factor	Rule
Standard (Shafi'i, Maliki, Hanbali)	1	Shadow = object height + noon shadow
Hanafi	2	Shadow = 2× object height + noon shadow

Set it with muslimtify madzhab shafi or hanafi. The default is shafi (Standard).

Kemenag, the default

Kemenag (the Indonesian Ministry of Religious Affairs) is the default because Muslimtify originated in Indonesia and Kemenag is a well-validated, widely-used standard there. Its parameters:

• Fajr angle 20°, Isha angle 18° (shared with JAKIM and MUIS).
• Ihtiyat: +2 minutes on all prayer times, −2 minutes on sunrise.
• Rounding: always rounds up (ceiling) to the next minute.

Academic comparisons of calculation against observation in Indonesia find differences of only 0–3 minutes, which is considered within acceptable limits.

Accuracy and tolerance

No major authority publishes a formal, quantified accuracy standard. In practice:

• The general jurisprudential consensus is that ±5 minutes from the "true" time is acceptable.
• A few methods carry a small precautionary ihtiyat buffer (Kemenag ±2, Jordan ±5), most apply none.
• Muslimtify's underlying astronomical model is accurate to roughly 4 seconds of time, so the choice of method (its Fajr/Isha angles) has far more effect on the result than the algorithm itself.

If your calculated times differ slightly from a local mosque's printed schedule, that is expected: mosques often apply their own offsets. You can match them with the per-prayer offset in Configuration.

High latitudes

At high latitudes (roughly above 48–50° N/S) the sun may never reach the required depression angle in summer, so the standard Fajr/Isha formula has no solution. When that happens, Muslimtify falls back to the angle-based approximation: it treats the twilight angle as a fraction of the night and places Fajr and Isha that fraction before sunrise / after sunset. If you live at a high latitude and see unusual Fajr or Isha times around the solstices, this is why.

Custom method

If none of the built-in methods fits, set a custom one directly in config.json:

"calculation": {
  "method": "custom",
  "madhab": "shafi"
}

Then provide your own fajr_angle and isha_angle values (in degrees). See Configuration.