Prayer Times Calculator
Accurately calculate prayer times for your location
Calculate Prayer Times
What is “Calculate Prayer Times”?
To calculate prayer times means to determine the specific times of the day when Muslims perform their five daily obligatory prayers (Salah): Fajr, Dhuhr, Asr, Maghrib, and Isha. These times are not fixed but vary daily and depend on the position of the sun relative to the observer’s location on Earth, which is determined by latitude, longitude, and the date.
Anyone who wants to observe the five daily prayers at their prescribed times needs to know or calculate prayer times. This includes Muslims all over the world, travelers, and those living in areas where local mosques may not be easily accessible or do not announce prayer times audibly for all prayers.
Common misconceptions include the idea that prayer times are the same every day or the same everywhere within a time zone. In reality, they change daily due to the Earth’s tilt and orbit, and vary significantly with latitude and longitude. Using a reliable tool to calculate prayer times is essential for accuracy.
“Calculate Prayer Times” Formula and Mathematical Explanation
The process to calculate prayer times involves several astronomical calculations:
- Julian Date (JD): The date is converted to a Julian Date, which is the number of days since noon Universal Time on January 1, 4713 BCE.
- Solar Declination (δ): This is the angle between the rays of the Sun and the plane of the Earth’s equator. It varies throughout the year from about -23.45° to +23.45°.
- Equation of Time (EoT): This is the difference between apparent solar time (as shown by a sundial) and mean solar time (as shown by a clock). It arises because of the Earth’s elliptical orbit and axial tilt.
- Time of Solar Noon (Dhuhr): This is when the sun reaches its highest point in the sky. It’s calculated as 12:00 – EoT (adjusted for longitude and timezone).
- Hour Angle (H): For other prayer times (Fajr, Sunrise, Asr, Maghrib, Isha), we need to find the time when the sun is at a specific angle below or above the horizon. The hour angle is calculated using the formula:
H = arccos((-sin(α) – sin(φ)sin(δ)) / (cos(φ)cos(δ)))
where α is the sun’s angle for the specific prayer, φ is the latitude, and δ is the solar declination. - Prayer Time Calculation: The time for each prayer is then calculated based on Dhuhr time and the hour angle H (converted from degrees to hours). For instance, Fajr time = Dhuhr – H(Fajr)/15, Isha time = Dhuhr + H(Isha)/15 (with adjustments for timezone and longitude). Asr time depends on the length of the shadow, which relates to the sun’s altitude angle.
Variables Table:
| Variable | Meaning | Unit | Typical Range |
|---|---|---|---|
| φ (phi) | Latitude | Degrees | -90 to +90 |
| λ (lambda) | Longitude | Degrees | -180 to +180 |
| TZ | Timezone Offset | Hours | -12 to +14 |
| Date | Gregorian Date | – | – |
| δ (delta) | Solar Declination | Degrees | -23.45 to +23.45 |
| EoT | Equation of Time | Minutes | -16.4 to +14.3 |
| α (alpha) | Sun’s Angle for Prayer | Degrees | Varies by method (e.g., -18° for Fajr MWL) |
| H | Hour Angle | Degrees | 0 to 180 (for one side of noon) |
Variables used to calculate prayer times.
Practical Examples (Real-World Use Cases)
Example 1: Calculating Prayer Times for Riyadh
Someone in Riyadh, Saudi Arabia (Latitude: 24.7136° N, Longitude: 46.6753° E, Timezone: +3) wants to calculate prayer times for July 15, 2024, using the Makkah (Umm al-Qura) method and Standard Asr.
- Inputs: Latitude=24.7136, Longitude=46.6753, Timezone=3, Date=2024-07-15, Method=Makkah, Asr=Standard.
- The calculator would process these and provide times for Fajr, Sunrise, Dhuhr, Asr, Maghrib, and Isha specific to Riyadh on that day.
Example 2: Calculating Prayer Times for London during Winter
A person in London, UK (Latitude: 51.5074° N, Longitude: 0.1278° W, Timezone: 0) wants to calculate prayer times for December 20, 2024, using the MWL method and Hanafi Asr, with Angle Based high latitude rule due to shorter days.
- Inputs: Latitude=51.5074, Longitude=-0.1278, Timezone=0, Date=2024-12-20, Method=MWL, Asr=Hanafi, HighLat=AngleBased.
- The calculator will provide the prayer times, adjusting for the high latitude if necessary based on the rule selected.
How to Use This “Calculate Prayer Times” Calculator
- Enter Location: Input your Latitude and Longitude. Positive values for North and East, negative for South and West.
- Set Timezone: Enter your local timezone offset from UTC.
- Select Date: Choose the date for which you want to calculate prayer times.
- Choose Method: Select a calculation method from the dropdown. Different regions and communities follow different methods.
- Select Asr Method: Choose between Standard and Hanafi for Asr calculation.
- High Latitude Rule: Select a rule if you are at a high latitude (above ~48 degrees).
- Calculate: Click “Calculate Times”. The results will display below, including a table of prayer times and a chart.
- Read Results: The table shows the times for each prayer. The primary result highlights Dhuhr time, and intermediate values show key astronomical data.
- Copy Results: Use the “Copy Results” button to copy the times and parameters.
Use the calculated times to plan your daily prayers and activities around them. Understanding how to calculate prayer times helps in adhering to prayer schedules accurately.
Key Factors That Affect “Calculate Prayer Times” Results
- Latitude: Your north-south position greatly affects the sun’s path and thus the times, especially at higher latitudes where day/night lengths vary dramatically.
- Longitude: Your east-west position within a timezone determines the local solar noon and other times relative to the timezone’s mean solar time.
- Date: The time of year changes the sun’s declination, altering the length of the day and the sun’s altitude, which directly impacts when we calculate prayer times.
- Calculation Method: Different methods use different angles for Fajr and Isha (and sometimes Maghrib), leading to variations in these times.
- Asr Juristic Method: The Standard (Shafii, Maliki, Hanbali) and Hanafi methods define Asr based on different shadow lengths, resulting in different Asr times.
- Timezone: The local time is derived by adjusting the calculated UTC prayer times by the timezone offset.
- High Latitude Rule: At latitudes above ~48°, twilight may merge or last all night in summer. High latitude rules adjust Fajr and Isha times to be reasonable.
- Altitude: Higher altitudes can slightly affect sunrise and sunset times, though most calculators assume sea level.
Being aware of these factors helps in selecting the right settings to accurately calculate prayer times for your specific circumstances.
Frequently Asked Questions (FAQ)
- Why are there different methods to calculate prayer times?
- Different methods use different conventions for the sun’s angle below the horizon for Fajr (dawn) and Isha (nightfall) based on various scholarly interpretations and observations.
- How accurate is this prayer times calculator?
- It uses standard astronomical formulas and well-known calculation methods. Accuracy depends on correct input of latitude, longitude, timezone, and method choice. It aims to be as accurate as the methods themselves.
- What is the difference between Standard and Hanafi Asr times?
- Standard (Jumhoor) Asr time is when the shadow of an object is equal to its length plus the shadow at noon. Hanafi Asr time is when the shadow is twice its length plus the shadow at noon, making it later.
- What if I am at a very high latitude?
- Use the “High Latitude Rule” setting. “Angle Based” adjusts angles, while “One Seventh” or “Middle of the Night” set Fajr/Isha based on night duration, for when normal twilight signs are absent or prolonged.
- Can I use this to calculate prayer times for any date?
- Yes, you can select past or future dates to calculate prayer times.
- Why is Maghrib time often close to sunset?
- Maghrib prayer time begins just after the sun completely sets below the horizon. Some methods add a few minutes of precaution.
- Does the calculator account for Daylight Saving Time (DST)?
- You need to input the correct timezone offset, including any DST adjustments. If your timezone is UTC-7 during DST, enter -7.
- What if my city is not listed or I don’t know my coordinates?
- You can easily find your latitude and longitude by searching for your city name + “coordinates” on a search engine or map service.