Prayer Times: How They Are Calculated and Read Right

The five prayer times and their windows

Prayer times mark when each of the five daily prayers may be performed. Every prayer has a window, a span of time in which it should be prayed, that opens at one moment and closes at another. The five are Fajr, Dhuhr, Asr, Maghrib, and Isha, in the order they fall across the day and night. Before we get into the calculation, it helps to fix the plain shape of each window in your mind, because the whole system of calculation is really just a precise way of finding these moments.

• Fajr begins at true dawn, the first spread of light along the horizon, and its window ends just before the sun rises. It is prayed while the sky is still dim.
• Dhuhr begins just after the sun passes its highest point at midday and starts to decline. Its window runs through the early afternoon until Asr begins.
• Asr begins in the afternoon, at a point set by the length of shadows, and its window continues until close to sunset.
• Maghrib begins just after the sun has fully set below the horizon. Its window is shorter than the others, so it rewards being ready.
• Isha begins once the red glow of twilight has left the sky and night has settled in. Its window extends through the night.

Notice that not one of these is tied to a fixed hour on the clock. Fajr is not "5 a.m." and Maghrib is not "6 p.m." Each one is tied to something the sun is doing: rising, reaching its peak, casting a shadow of a certain length, setting, or leaving the sky dark. That single fact is the key to everything that follows. Once you understand that prayer times track the sun, the rest of this guide, including why the times change and why apps sometimes disagree, becomes easy to follow.

The obligatory nature of these fixed times is rooted in the Quran itself. In Surah An-Nisa the believers are reminded that the prayer has been prescribed at appointed times (see Quran 4:103). Elsewhere the day's rhythm of worship is tied to the sun's movement, for example in the instruction to establish prayer at the decline of the sun until the darkness of the night, and the recitation at dawn (see Quran 17:78). The scholars of Islam took these anchors and, across centuries, worked out the precise boundaries of each window from the visible signs in the sky. Modern calculation simply reproduces those same signs with astronomy.

Why prayer times follow the sun, not the clock

Here is the reason a single printed timetable cannot serve you forever. The earth spins on a tilted axis while it travels around the sun, and because of that tilt the sun's daily path across your sky is never quite the same two days running. In summer the sun climbs higher and stays up longer, so dawn comes early and sunset comes late. In winter the sun stays low and the day is short, so dawn is late and sunset is early. The prayer windows, being pinned to dawn, midday, shadow length, sunset, and twilight, slide along with it.

The shift is gradual, usually a minute or two per day, which is why you might not notice it from one morning to the next. Over a few weeks, though, it becomes obvious. Fajr in June and Fajr in December can be hours apart. This is exactly why a good prayer time source recalculates every single day rather than storing one fixed schedule. It is also why the times you pray by depend so heavily on where you stand on the earth.

Two things about your location matter. Your latitude, how far north or south you are, changes how high the sun climbs and how long twilight lasts. Near the equator the sun rises and sets quickly and twilight is short, so the prayer windows are fairly stable through the year. Far to the north or south, the days stretch and shrink dramatically with the seasons, and twilight can drag on for a long time in summer. Your longitude, how far east or west you are, shifts the actual clock time of every event, because the sun reaches your meridian earlier or later than it reaches a city in the next time zone.

Put those together and you can see why a schedule made for one city is wrong for another, even a nearby one, and why last year's timetable is wrong for this year. Accurate prayer times are always a calculation for a specific place on a specific date. There is nothing mysterious in it. It is the same astronomy that predicts sunrise and sunset, applied to the moments the prayer windows begin.

How prayer times are calculated, prayer by prayer

Let us walk through each prayer and the sign that sets its time. You do not need any mathematics to follow this. The point is to understand what each window is anchored to, so you can trust the number your app gives you and know what to adjust if it looks off.

Dhuhr and the sun's highest point

The easiest one to grasp is Dhuhr, because it is anchored to solar noon, the moment the sun crosses the meridian and sits at its highest point in your sky. This is not the same as 12:00 on the clock; true solar noon can be well before or after that depending on your longitude within your time zone and a small yearly wobble in the sun's timing. Dhuhr time begins just after the sun has passed that peak and visibly starts to decline. Because solar noon is the pivot of the whole day, every other calculation, including the shadow that sets Asr, is measured from around it.

Asr and the length of a shadow

Asr is set by shadows. As the afternoon wears on and the sun sinks toward the west, the shadow cast by an upright object grows longer. Asr begins when that shadow reaches a defined length relative to the object and to the short shadow it had at midday. This is why Asr time depends on the season: in winter, when the sun stays low, shadows are already long and Asr comes relatively soon after Dhuhr; in summer, with the sun high overhead, it takes longer for shadows to stretch out, so Asr falls later in the afternoon. There are two accepted ways to define the exact shadow length, which we cover in the Asr section below, and that choice is one of the main reasons two timetables can differ.

Maghrib and sunset

Maghrib is the most intuitive of all: it begins at sunset, the moment the top edge of the sun dips below the horizon and disappears. Because sunset is a sharp, visible event, Maghrib is the time that different calculation methods agree on most closely. The small variations that remain come from how the horizon is modeled, tiny corrections for the bending of light near the horizon, and elevation, since standing on a hill lets you see the sun a little longer than someone at sea level. For most people in most places, the calculated Maghrib matches the sunset they can see out the window, which is a nice check that the times are set correctly. If you want the deeper detail on this one prayer, we wrote a full guide on what time Maghrib is and how it is set.

Fajr and Isha, set by twilight

Fajr and Isha are the two that need the most explaining, and they are where nearly all the disagreement between methods comes from. Both are tied to twilight rather than to a sharp event like sunset. After the sun sets, the sky does not go dark at once; sunlight keeps scattering through the upper atmosphere and the horizon glows for a while. That fading glow is the evening twilight, and Isha begins when it has gone and the sky is properly dark. In the same way, before the sun rises the sky begins to lighten while the sun is still below the horizon, and Fajr begins at true dawn, the first honest spread of light across the horizon.

The trouble is that "the sky is dark enough" and "dawn has truly begun" are moments of changing light, not the crisp instant of a sunrise. To turn them into a precise calculable time, they are defined by how far the sun has sunk below the horizon: an angle. That is the whole idea behind Fajr and Isha angles, and it is worth its own section.

What Fajr and Isha angles mean

An angle here is just a way of describing how low the sun is beneath the horizon. When the sun sits right on the horizon, that is zero degrees, which is sunrise or sunset. As it sinks further down out of sight, the number of degrees below the horizon grows, and the sky keeps getting darker. Fajr and Isha are each defined at a chosen depth of the sun below the horizon, because that is the reliable, measurable stand-in for the light level the eye would see.

A widely used value for Fajr is 18 degrees below the horizon, the point astronomers call the end of astronomical twilight, when the sky is fully dark before the first light of dawn. So Fajr, defined at an 18 degree angle, begins the instant the rising sun climbs back up to 18 degrees below the horizon on its way toward sunrise. Isha, similarly, can be defined when the setting sun has dropped to a certain angle below the horizon and the evening twilight is judged to have ended. Some methods use 18 degrees for Isha as well; others use 17 degrees or a different value.

Why does an angle of just one degree matter to your prayer time? Because near the horizon the sun moves through those low angles slowly, and the exact moment the light reaches the chosen level can shift the clock time by several minutes or more, and much more at high latitudes where the sun travels at a shallow angle. That is the entire source of the Fajr and Isha spread you see between methods. Everyone agrees Fajr is true dawn and Isha is the end of twilight. They differ only in which precise angle best captures those moments, and reasonable scholars and organizations have landed on slightly different numbers.

None of this should worry you. These are small, honest differences between valid ways of pinning down a moment of changing light, not a matter of one being right and the others wrong. The sensible approach is to use the method your local community and mosque use, so that you are praying together with the people around you, and to leave the fine astronomy to the app.

Calculation methods: MWL, ISNA, Umm al-Qura and more

Because Fajr and Isha depend on a chosen angle, a handful of well-known organizations have each published a set of parameters, and these are what your app calls calculation methods. Picking a method just tells the app which Fajr and Isha angles, and sometimes which Isha rule, to use. Here are the ones you will most often see in a prayer time app, described plainly and without judgment. All of them are used by large communities.

• Muslim World League (MWL). A widely used global default. It uses an 18 degree angle for Fajr and a 17 degree angle for Isha. Many communities outside a single country's authority use it as a sensible general standard.
• Islamic Society of North America (ISNA). Common across the United States and Canada. It uses a 15 degree angle for both Fajr and Isha, which tends to give a somewhat later Fajr and earlier Isha than the 18 degree methods.
• Umm al-Qura. The method used in Saudi Arabia. It uses an 18.5 degree angle for Fajr, and for Isha it uses a fixed interval after Maghrib rather than an angle, a set number of minutes that is longer during Ramadan.
• Egyptian General Authority of Survey. Long used in Egypt and parts of Africa and beyond. It uses a 19.5 degree angle for Fajr and a 17.5 degree angle for Isha.
• University of Islamic Sciences, Karachi. Common across South Asia. It uses an 18 degree angle for both Fajr and Isha.

You may also see regional methods for the Gulf, Iran, Singapore, France, Turkey, and others, each with its own tuned parameters for the local sky and the local authority. The naming can look intimidating in a settings menu, but the practical takeaway is simple: these are all accepted, and the differences between them are on the order of minutes for Fajr and Isha and essentially nothing for Dhuhr, Asr by a given school, and Maghrib.

So which do you pick? The most useful rule is to match your local mosque. Find out which method the mosque you pray at, or the main Islamic authority where you live, uses, and set your app to the same. That way your Fajr and Isha line up with the community, and when you go to pray in congregation the times agree. If you have no local reference, a common global choice like the Muslim World League method is a reasonable default until you learn what your community follows.

Treat that table as a map, not a test. You do not need to memorize the angles. You just need to know that these named methods exist, that your app lets you choose one, and that the right choice is the one your community prays by. Set it once and you can forget it.

Asr: the Shafi'i and Hanafi times

Asr deserves its own section because, unlike Fajr and Isha where the differences come from calculation authorities, the Asr difference comes from jurisprudence, and it is the one most likely to surprise a new user who sees two "correct" Asr times that are noticeably apart. Both are valid positions held by great scholars, and neither app is wrong.

Recall that Asr is defined by the length of an object's shadow. At solar noon an upright stick casts its shortest shadow of the day. As the afternoon goes on, that shadow lengthens. The two views differ on how long the shadow must grow before Asr begins.

• The majority (Shafi'i, Maliki, Hanbali) view. Asr begins when the shadow of an object equals the object's own height, added to whatever shadow it already had at midday. Apps often label this "Standard" or "Shafi'i." This gives the earlier of the two Asr times.
• The Hanafi view. Asr begins when the shadow reaches twice the object's height, again added to the midday shadow. Apps label this "Hanafi." Because the shadow has to grow longer, Hanafi Asr begins later, sometimes by a fair margin, especially in winter when the sun is low.

This is why a friend across the room might see an Asr time on their phone that is thirty or forty minutes different from yours, with both phones perfectly accurate. One is set to the standard method and the other to Hanafi. The fix is not to argue with the app but to set the Asr method that matches how you and your community pray. If you follow the Hanafi school, choose Hanafi; if you follow one of the others, choose the standard setting. As always, for your own practice follow qualified scholars and the way of your local mosque.

Why two prayer time apps can disagree

By now the main answer should already be clear, but let us gather it in one place, because "why does my app show a different time than my friend's" is one of the most common questions new users ask, and the honest answer is reassuring. The prayers, their order, and the sun-based logic behind them are agreed upon across the Muslim world. The disagreements you see on screens come from settings, not from anyone being wrong.

1. Different Fajr and Isha angles. One app is on ISNA at 15 degrees, another on the Muslim World League at 18 degrees. Their Fajr and Isha will differ by minutes. This is the single most common cause.
2. Different Asr method. One is set to standard, the other to Hanafi. Their Asr times differ, sometimes substantially.
3. Different location. If one app is using a slightly different city, a saved location from a past trip, or a coarse network location instead of GPS, its whole timetable shifts. Longitude changes the clock time of every event.
4. Rounding and safety margins. Some apps round to the nearest minute, some add a small precautionary buffer to a window, and some show sunrise as the end of Fajr while others show a moment just before. Small display choices create small gaps.
5. High-latitude rules. In places where twilight behaves strangely in summer, apps apply different rules to estimate Fajr and Isha, which we cover next. Two sensible rules can give two different answers.

The practical response to all of this is calm and simple. Decide which calculation method and Asr school your community follows, set your app to exactly that, and make sure it is using your correct location. Once you do, your times will agree with the people you pray beside, which is really the point. If you ever want to compare apps fairly, we lay out what actually matters in a good one in our guide to the best Muslim prayer app.

How to get accurate times for your location

Accurate prayer times come down to three inputs done right: the correct location, the right method, and the current date. Get those three lined up and the astronomy takes care of the rest. Here is how to check each one.

Set the location precisely. Let the app use your device's GPS location, or set your city by hand if you prefer not to share location. The finer the location, the more exact the times, because both your longitude and your latitude feed the calculation. Watch out for a stale location saved from a trip, or a location that snapped to a large nearby city instead of your town. If your Maghrib time is a few minutes off from the sunset you can see with your own eyes, a wrong location is the first thing to check.

Choose the method your community uses. As covered above, set the calculation method (for Fajr and Isha) and the Asr school to match your local mosque or national authority. This is a one-time setting. Once it is right, you are praying on the same times as the people around you.

Let it recalculate daily. Because the times move with the sun through the year, a good app recomputes every day for the new date automatically. You should never be praying by a screenshot from last month or a printed sheet from last year. If you keep a paper timetable as a backup, make sure it is the current one for your city.

Sanity-check against the sky. You have a free reference built into the world. Maghrib should match the sunset you can see, and Fajr should match the real spread of dawn light if you are ever up to notice it. If the calculated times track the sky, your setup is sound. If Maghrib is minutes off from actual sunset, revisit your location setting. Where the natural signs can be seen, they remain the reference that the calculation is trying to reproduce.

Getting your direction right belongs in the same setup pass. Prayer times tell you when; the Qibla tells you which way to face. If you are configuring an app for a new city, set both at once, and see our guide on finding the Qibla direction accurately so your compass points true.

The high-latitude problem in short nights

There is one situation where the plain angle method runs into real trouble, and it is worth knowing about even if you do not live there, because it explains some odd-looking times. Far to the north or south, in the height of summer, the sun may not sink far enough below the horizon for the sky to reach the darkness that defines Fajr and Isha. The 18 degree point, for example, may simply never happen; twilight from the setting sun blends into the twilight of the rising sun, and there is no true night. In such places the ordinary calculation cannot produce a real Fajr or Isha time, so a sensible estimate has to stand in.

Scholars and app makers use several recognized high-latitude rules to handle this. Some estimate the night by dividing the time between sunset and sunrise into portions and placing Isha and Fajr at set fractions of it. Some hold the angle to the last date it worked and carry that interval forward. Some use the timings of the nearest latitude where the angle still occurs. Each of these is a reasoned way to give people at high latitude a workable, consistent timetable when nature does not provide a clear sign.

If you live at a high latitude, the important thing is to choose a high-latitude rule, and ideally the one your local Islamic authority recommends, so that your Fajr and Isha are both reasonable and in step with your community. This is another area where the right answer for your situation is best taken from qualified scholars and your local mosque rather than settled alone. A good app will offer these rules in its settings and let you follow your community's choice.

A practical system for never missing a prayer

Understanding the times is one half of the goal. Actually stopping to pray when each window opens is the other, and it is the part that everyday life keeps interrupting. Knowing when Asr comes in does you no good if the afternoon swallows it whole before you notice. A small, reliable system fixes this, and none of it requires willpower you do not have. It just needs a nudge at the right moment.

1. Turn on the azan or a prayer notification. The single most effective habit tool is a sound or alert the moment each time enters. The call to prayer has pulled Muslims to worship for centuries, and a phone that gives you the azan or a gentle reminder at the start of each window turns a good intention into a kept one. Let the app tell you; do not rely on remembering.
2. Pray at the start of the window when you can. Praying early, near the opening of the time, is encouraged and it removes the risk of the window closing while you are busy. Maghrib especially has a shorter window, so treating its arrival as an immediate cue is wise.
3. Use a pre-adhan warning for the tight ones. A short heads-up a few minutes before Maghrib or Fajr, on top of the alert at the actual time, gives you space to make wudu and be ready. Fajr, being the most missed prayer, benefits from a reliable alarm you actually respect.
4. Know the last third for the night prayers. If you are working toward the voluntary night prayer, an app that shows you when the last third of the night begins makes it far easier to plan. We wrote separately about how the five obligatory windows fit together, which pairs well with this if you are still learning the sequence, in our guide on how to pray in Islam.
5. Keep the times visible. A widget or a glanceable next-prayer countdown means you always know how long is left in the current window. Seeing "Asr, 40 minutes left" is often the difference between praying now and forgetting.

The common thread is that you should not carry the timing in your head. Offload it to a reliable source that recalculates every day and alerts you at the right moment, and spend your attention on the prayer itself. That is precisely the job a prayer time app should do, quietly and without getting in your way or trying to sell you anything.

How Niyyara keeps your times accurate

Niyyara is a free, private, ad-free companion built to do exactly what this guide describes. It calculates accurate prayer times for your exact location and the current date, so Fajr, Dhuhr, Asr, Maghrib, and Isha are always right for where you actually are and for today, not for some default city or some past week. You set your calculation method and your Asr school once to match your community, and from then on the times simply track the sun for you.

It sounds the azan when each time enters, which for many people is the nudge that turns knowing the times into actually praying them. It shows the next prayer and how long is left in the current window, so a glance tells you where you stand in the day. It includes an accurate Qibla compass so you face the right way, the full Quran with audio, everyday duas, the 99 names of Allah, a tasbih for remembrance, the Islamic calendar, and a worship tracker to watch your consistency grow. For high latitudes, it offers the recognized rules so your Fajr and Isha stay reasonable through the short summer nights.

Because it is completely free, with no subscriptions and no ads, nothing stands between you and your worship. There is no paywall in front of the azan, no banner interrupting your dua, no upsell when you open the app to check Maghrib. Worship should never feel like a product being sold to you, and it does not have to be. Niyyara stays out of the way and simply gives you accurate prayer times, the call to prayer, and the direction to face, so you can get on with praying on time.

You now have the whole picture: what the five prayer windows are, why they follow the sun rather than the clock, how each is calculated, what the Fajr and Isha angles mean, why the named methods and the two Asr views differ, why two honest apps can disagree, and how to make sure your own times are accurate. Set your location, choose your community's method, turn on the azan, and let the calculation carry the timing. May Allah accept your prayers and make each one easy to keep. The next window is coming; be ready for it.