Accurate Prayer Times: Why Fajr and Isha Differ Between Apps
Open two different prayer-time apps on the same day, in the same city, and Fajr can differ by ten minutes — Isha sometimes by more. That doesn't mean one app is simply wrong. Each one uses a slightly different astronomical angle to mark the start of Fajr and the end of Isha, and that difference genuinely exists between the astronomical and religious authorities different countries follow.
Why do prayer times differ between apps?
Prayer-time calculation is based on the sun's position relative to the horizon for your location and date, using standard astronomical formulas long established and used by most serious prayer-time apps. Dhuhr, Asr, and Maghrib are derived almost directly from the sun's position and barely vary between apps. Fajr and Isha are different: they're set by the angle of the sun below the horizon at twilight, and that specific angle varies by which astronomical or religious authority defined the method — some use 18 degrees, others 15 or 17 — and that small angle difference translates into ten minutes or more on the clock.
That's the real reason apps disagree: each one defaults to a different calculation method — Umm al-Qura, the Muslim World League, the Egyptian General Authority, the University of Karachi, and other methods used across different regions — and rarely tells you clearly which one it's using by default.
What Sahel's prayer times tool does
The prayer times tool calculates the five daily prayers and sunrise for your location, and lets you pick the calculation method yourself from ten recognized options instead of silently defaulting to one without explaining it. That means you can match the result to whatever your local mosque or country follows, instead of guessing why your number differs from a friend's.
Why does Asr specifically differ?
Asr's start depends on shadow length: one school of thought marks it when a shadow equals the height of the object casting it, another when the shadow reaches twice that height — a difference in jurisprudence, unrelated to the accuracy of the astronomical calculation itself. The tool lets you pick the madhab that applies to you, which shifts only Asr's time according to your choice while every other prayer stays the same.
Steps to use it
- Open the prayer times tool and allow location access, or pick your city from the list instead.
- Review the five prayer times shown automatically, along with a countdown to the next one.
- From the dropdown, pick the calculation method your country or mosque follows if it differs from the default.
- Pick the madhab that applies to you if you want to adjust Asr specifically.
- Move between previous or upcoming days if you need times for a day other than today.
A real case
Someone is travelling from Riyadh to Cairo for three days of work and wants Cairo's prayer times before the trip, to plan meetings around them. Instead of manually working out the time difference between the two cities and calculating it themselves, they open the tool and pick "Cairo" from the ready-made city list — the five times shown are in Cairo's own local time, not the phone's, which is still set to Riyadh — so the schedule is planned accurately before they've even landed.
Later, a friend opens a different app and finds Isha twenty minutes later than what Sahel's tool shows. Comparing the two, they discover the other app defaults to the Moonsighting Committee method with a deeper twilight angle, while Sahel's tool was set to Umm al-Qura by default — so they agree to pick the same method in both, matching the numbers instead of doubting either one's accuracy.
Frequently asked
Which calculation method should I choose?
Best to match whatever your local mosque or country's official body follows. Umm al-Qura is the method officially used in Saudi Arabia specifically, while other countries follow different ones. If you're unsure, ask people around you what's typically used in your area.
Does the tool need a constant internet connection?
The calculation itself runs on your device once your location is set, with nothing uploaded to any server or any need for a continuous connection afterward.
What's the difference between using my current location and picking a city?
Your current location calculates times for where you actually are, right now. Picking a city is useful when you want times for somewhere else — a city you're about to travel to — shown in that city's own local time rather than your device's.
Are prayer times the same every day?
No, they shift gradually day to day because the sun's position changes with the seasons, which is why the tool recalculates the current day every time you open it, and also lets you navigate to see other days, past or upcoming.
Does the countdown keep working if I close and reopen the app?
Yes, the countdown is recalculated fresh the moment you open the tool, based on the actual time and that day's prayer times, so there's no need to keep the page open the whole time to track it accurately.
Try the tool
Open the prayer times tool, pick the calculation method and madhab that match you, and get your five accurate prayer times wherever you are.
