Understanding Prayer Times

How Prayer Times Work

Muslims observe five obligatory daily prayers — Fajr, Zuhr (Dhuhr), Asr, Maghrib, and Isha — each tied to the position of the sun. Because the sun's path changes with the seasons and varies by geographic location, prayer times shift throughout the year and differ from city to city. This is why a prayer timetable for London looks different from one for Karachi, even on the same day.

Prayer time calculators use astronomical formulas to determine exactly when each prayer window opens based on your latitude, longitude, date, and the calculation method selected. This guide explains what each prayer time represents, how the calculations work, and why you might see slightly different times across different apps or websites.

The Five Daily Prayers

Fajr — The Dawn Prayer

Fajr begins at "true dawn" — when the first horizontal light appears on the eastern horizon, before the sun itself is visible. Different calculation methods define this using different sun depression angles: ISNA (Islamic Society of North America) uses 15°, the Muslim World League uses 18°, and the Egyptian General Authority uses 19.5°. A higher angle means an earlier Fajr time. This is the main reason Fajr times differ between apps.

Sunrise (Shurooq)

Sunrise is not a prayer time. It appears in timetables because it marks the end of the Fajr prayer window. The Fajr prayer should be completed before sunrise begins.

Zuhr / Dhuhr — The Noon Prayer

Zuhr begins shortly after solar noon — the moment the sun reaches its highest point in the sky and begins to descend. Most calculation methods add a small safety margin (typically 1–5 minutes) after solar noon to ensure the sun has clearly passed the meridian.

Asr — The Afternoon Prayer

Asr timing depends on the length of an object's shadow relative to the object itself. This is where the primary difference between the Shafi and Hanafi schools of jurisprudence appears — see the madhab differences section below.

Maghrib — The Sunset Prayer

Maghrib begins at sunset — when the upper edge of the sun disappears below the horizon. This is one of the most consistent prayer times across different methods, since sunset is a directly observable event. In the Ja'fari tradition, Maghrib is observed approximately 15–20 minutes after sunset, when the redness has faded from the eastern sky.

Isha — The Night Prayer

Isha begins when the twilight has fully disappeared and the sky is dark. Like Fajr, different methods define this using different sun angles. Some methods (such as Umm al-Qura) use a fixed time interval after Maghrib rather than a sun angle calculation.

How Prayer Times Are Calculated

Modern prayer time calculators use the sun's position relative to the horizon to determine when each prayer window opens. The key inputs are your geographic coordinates (latitude and longitude), the date, and the calculation method. The sun's declination angle and the equation of time are computed for the given date, and then trigonometric formulas determine the exact moment the sun reaches the required angle below the horizon.

Zuhr, Sunrise, and Maghrib are relatively straightforward — they correspond to solar noon, sunrise, and sunset, which are standard astronomical calculations. Fajr and Isha are more complex because they depend on the angle of twilight, which is defined differently by different Islamic authorities. Asr depends on shadow length, which varies by jurisprudential convention.

This tool uses the open-source adhan.js astronomical library, which implements the standard prayer time equations used by major Islamic organisations worldwide.

Calculation Methods

Different Islamic authorities around the world have established their own parameters for calculating Fajr and Isha times. These methods differ primarily in the sun depression angles they use. A larger angle means an earlier Fajr and a later Isha.

Because ISNA uses a 15° angle while the Egyptian method uses 19.5°, Fajr under the Egyptian method can be 20–30 minutes earlier than under ISNA at the same location. This is the single biggest reason two prayer apps may show different Fajr times for the same city.

How This Tool Selects Your Method

When you open this tool, it detects your geographic location and automatically selects the calculation method most commonly used in your region. You do not need to configure anything manually — but you can verify which method is being used in the information panel below the prayer times.

Madhab Differences in Prayer Times

This tool supports three jurisprudential conventions for Asr and Maghrib timing. You can switch between them using the toggle buttons on the calculator page.

Shafi (also Maliki and Hanbali)

Asr begins when the shadow of an object equals the length of the object itself (plus the shadow length at solar noon). This produces an earlier Asr time. This is the default setting.

Hanafi

Asr begins when the shadow of an object equals twice the length of the object (plus the shadow length at solar noon). This produces an Asr time approximately 30–60 minutes later than the Shafi calculation, depending on the season and location.

Ja'fari (Fiqh Jafariya)

Asr timing is similar to the Shafi convention. The main difference is in Maghrib: in the Ja'fari tradition, Maghrib is observed approximately 15–20 minutes after sunset, when the redness has faded from the eastern sky, rather than at the moment of sunset. When Ja'fari is selected, this tool uses the Tehran calculation method.

Tahajjud, Ishraq, and Voluntary Prayers

In addition to the five obligatory prayers, many Muslims observe voluntary prayers at specific times. This tool shows estimated times for several of these:

Tahajjud — the late-night voluntary prayer, observed during the last third of the night. The tool calculates the night period (Maghrib to Fajr) and identifies the final third.

Ishraq — a voluntary prayer observed approximately 15–20 minutes after sunrise, once the sun has risen well above the horizon.

These times are shown in the "Tahajjud / Ishraq / Night Prayer Times" section on the calculator page.

Why Your Times Might Differ From Another App

If you have ever compared two prayer time apps and seen different results for the same city, you are not alone. The most common reasons are:

Different calculation methods. An app using ISNA (15°) will show a later Fajr and earlier Isha than one using MWL (18°). This can mean differences of 15–30 minutes.

Different Asr jurisprudence. An app set to Hanafi will show Asr 30–60 minutes later than one set to Shafi.

Safety minutes (ihtiyat). Many mosques and some apps add 2–5 minutes of safety padding to calculated times as a buffer for atmospheric conditions. This tool shows raw calculated times without ihtiyat.

Altitude adjustments. Some apps adjust sunrise and sunset for the altitude of your location, while others assume sea level. This can shift Maghrib and Fajr by 1–3 minutes.

Daylight saving time. An app that does not correctly handle DST transitions may show times that are off by exactly one hour during part of the year.

Local mosque adjustments. Your neighbourhood mosque may publish slightly different times than any app, because they apply their own regional conventions or ihtiyat. This is normal and expected.