How we calculate prayer times & qibla

The short version

• Times and the qibla are computed on your device from your coordinates — they work fully offline and your location never leaves your phone.
• The astronomy is done with adhan, a widely used, open-source implementation of the standard prayer-time algorithms. It is the same well-reviewed engine that backs many trusted prayer apps.
• You choose the authority (calculation method), the Asr opinion (madhab), and, if needed, a high-latitude rule — and you can nudge any prayer to match your local masjid’s printed timetable.
• The qibla is the great-circle direction to the Ka’bah, corrected to true north; the compass shows a reliability indicator so you know when a reading is trustworthy.

How prayer times are determined

Five of the day’s times are fixed points in the sun’s daily path, computed from your latitude/longitude and the date:

• Sunrise and Maghrib (sunset) are the geometric rising and setting of the sun — they do not depend on any school or authority, so every correct calculator agrees on them to the minute.
• Dhuhr is solar noon (the sun crossing the meridian) plus a small safety margin.
• Fajr and Isha begin/end at twilight — defined by how far the sun is below the horizon. That angle is where recognized authorities differ (see below).
• Asr is defined by shadow length, which depends on the juristic opinion you follow (see “Asr” below).

Calculation authorities you can follow

A “calculation method” is simply the set of twilight angles published by a recognized authority. We expose the standard catalog; the Fajr/Isha values below are read directly from the calculation engine, so this table reflects exactly what the app uses:

Most North American families follow ISNA (15° / 15°), the default. If your community follows a different authority, pick it — the angle is the only thing that changes, and it only moves Fajr and Isha.

Asr (madhab)

Asr begins when an object’s shadow reaches a multiple of its own length plus its noon shadow. There are two long-standing opinions, both supported:

• Majority (Shāfiʿī, Mālikī, Ḥanbalī) — shadow = 1× object length. This is the earlier Asr and the default.
• Ḥanafī — shadow = 2× object length. This is the later Asr, and in summer it can be over an hour later than the majority time.

This is why two correct apps can show very different Asr times — they’re simply set to different schools, not in error.

High-latitude rule (Fajr & Isha)

On short summer nights — or far from the equator — the sun may never dip to the Fajr/ Isha angle, or twilight lasts much of the night. In those cases a high-latitude rule estimates the two times. It only affects Fajr and Isha, and only when the geometry actually requires it. The options:

• Auto (default) — uses the convention scholars recommend for your latitude. Below ~48° this is “middle of the night”; farther out it is “one-seventh of the night.”
• One-seventh of the night — keeps Fajr and Isha within the seventh of the night nearest dawn/dusk. Many North American masjids use this, which is why their printed Fajr/Isha can sit ~15–20 minutes inside the pure-angle time.
• Middle of the night — Fajr/Isha may not cross the midpoint between sunset and sunrise.
• Twilight angle — scales the limit by the method’s own Fajr/ Isha angles.

If your Fajr/Isha look off by ~15–20 minutes versus your masjid, switching to “one-seventh of the night” usually reconciles them.

Matching your local masjid

Even with the right authority, a masjid’s printed timetable may round, add a safety margin, or follow a local convention. So you can apply a per-prayer manual offset of up to ±60 minutes to any prayer. The adjusted time is what you see and what your reminders fire at — so the app can match your masjid exactly, to the minute.

Why our times might differ from another app

When two apps disagree, it is almost always one of four explainable reasons:

1. Different authority — a different Fajr/Isha angle (e.g. ISNA 15° vs. MWL 18°).
2. Different Asr school — majority vs. Ḥanafī.
3. Different high-latitude rule — the most common cause of a ~15–20 min Fajr/Isha gap.
4. Rounding or a manual offset — some timetables round to the minute or add a margin.

Sunrise, Dhuhr, and Maghrib depend only on the sun’s position, so if those match another source, the calculation engine is sound and any remaining difference is one of the choices above — all of which you control here.

The qibla direction

The qibla is the initial great-circle bearing from your location to the Ka’bah (21.4225°N, 39.8262°E) — the shortest path over the earth’s surface, which is the direction the majority of scholars and qibla tools use. It is computed with the same adhan library that produces the prayer times, so there is a single, consistent source of truth.

The bearing is relative to true north. A phone’s magnetometer reads magnetic north, which differs from true north by the local magnetic declination (often several degrees). When your device reports a true heading, we use it directly; when it can only report magnetic north, we apply the declination we last learned from your device so the needle still points at the real qibla rather than at magnetic north.

The qibla reliability indicator

A compass is only as good as the sensor reading behind it, so the qibla screen shows a status at the top so you are never misled by a poor read:

• Calibrating — the device hasn’t produced a stable heading yet. Move the phone in a figure-8 a few times.
• Low accuracy — the magnetometer is uncertain (often near metal, magnets, a case with a magnet, or a car). The needle may be off; re-calibrate and step away from interference.
• Good — the device reports a confident heading; the direction can be trusted.
• Bearing only — if location/compass access is off, we still show the exact numeric bearing from true north, which you can use with any standalone compass.

The bearing itself (the angle to the Ka’bah) is always exact — it is math. The reliability indicator is about whether your phone’s compass can be trusted to point you along that bearing right now.

Sources & privacy

• Astronomy & qibla: the open-source adhan library (calculation methods, Asr madhab, high-latitude rules, and qibla bearing).
• Everything is computed on your device. Your coordinates are used locally to calculate times and the qibla and are not shared for this purpose.