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Ramadan 2027

Methodology — How Every Time on This Site Is Calculated

Every time shown on this site is computed, not copied from a timetable. This page explains how, so you can judge how far to trust it and why it may differ from the timetable on your mosque wall.

The Ramadan date

The site uses 8 February 2027 as its current planning date for the first fast of Ramadan 1448 AH. Published future calendars, including Timeanddate, also currently list 8 February for a number of countries as a tentative date. It is not treated here as an official moon-sighting forecast. The confirmed beginning follows the recognised authority or method a community follows and may differ between countries.

The month is either 29 or 30 days. Nothing on this site states the number of fasts as a settled fact, because it is not knowable in advance.

Moon-sighting uncertainty

Authorities use different approaches to establishing a new lunar month. Some rely on local or national sighting reports, some accept reports from a wider region, and some incorporate astronomical criteria. This site does not predict an independent official start for every country. Its tables use a configurable planning date until the relevant authority announces the month.

Prayer-time calculation

Prayer times are derived from the sun’s position for a given latitude, longitude and date, using standard solar-position geometry:

  • Fajr — when the sun reaches a set angle below the horizon before sunrise. The angle depends on the convention chosen.
  • Sunrise and Maghrib — the geometric rising and setting of the sun’s upper limb, adjusted for atmospheric refraction and for the observer’s elevation where that is known.
  • Dhuhr — solar noon, when the sun crosses the local meridian, with a short margin added.
  • Asr — when an object’s shadow reaches a set multiple of its own length plus the shadow at noon. The standard convention uses one times; the Hanafi convention uses two. Both are used by large numbers of Muslims; neither is presented here as the correct one.
  • Isha — when the sun reaches a set angle below the horizon after sunset, or a fixed interval after Maghrib in conventions that use one.

Calculation methods

The Fajr and Isha angles are the main source of difference between one timetable and another. This site selects a default convention per country based on what is commonly used there, and where a tool allows it you can change the method yourself. Changing the method changes Fajr and Isha noticeably, Asr only if you switch conventions, and sunrise, Dhuhr and Maghrib barely at all.

No convention is universally correct. Local religious authorities and individual mosques often apply their own settings, and many add a safety margin of a few minutes to Fajr or hold Iftar slightly after the computed sunset. That is why a difference of a few minutes between this site and your mosque is expected and is not evidence that either is wrong.

Sehri and Iftar

Sehri (Suhoor) ends at the entry of Fajr, and Iftar begins at Maghrib. The site uses the computed Fajr and Maghrib times for your location. Some printed timetables also show an imsak time a few minutes before Fajr as a precaution; that is a margin, not the limit itself.

Fasting duration

The fasting duration for a day is the interval between that day’s Fajr and that day’s Maghrib for your location. It changes slightly from day to day through the month as the sun’s declination shifts, and it varies enormously by latitude — far more between two countries than between two calculation methods. At very high latitudes the geometric definitions break down for part of the year; where that happens the site says so rather than printing a number that has no meaning.

Time zones and daylight saving

Times are computed in UTC and then converted using the IANA time zone of the city, so daylight-saving transitions are handled by rule rather than by a fixed offset. Countdowns are computed against your own location’s zone, never against the server’s.

Location detection

Location is resolved in the least intrusive order that works:

  1. A city you picked before, remembered in your own browser.
  2. Your browser’s time zone, which needs no permission and identifies only the zone.
  3. Device coordinates from the browser Geolocation API — only after you explicitly ask for it, or automatically when your browser reports that you already granted permission. The browser also reports an accuracy estimate in metres where available.
  4. Manual city search, always available.

Coordinates are used in your browser to recalculate the Ramadan countdown and daily solar times. They are not sent to this site’s server by the location feature. Browser geolocation is not guaranteed to be ‘pinpoint’: GPS, Wi-Fi and cellular positioning can each have different accuracy, so the interface shows the browser-reported accuracy when available. If permission is unavailable, time-zone estimation and manual city selection remain available.

Countdowns

The homepage Ramadan countdown targets local Maghrib on the evening before the projected first fast, because the Islamic date begins at sunset. The target is recalculated in the browser from the visitor’s coordinates and IANA time zone. Sehri and Iftar counters use the same location for Fajr and Maghrib. Geolocation improves the solar-time target; it cannot make an unconfirmed future moon-sighting date certain.

Calendar generation

A generated calendar is the day-by-day application of everything above: for each day of the projected month, the Fajr, sunrise, Dhuhr, Asr, Maghrib and Isha times for your coordinates, plus the fasting duration. A downloaded calendar states the location, the year, the time zone and the calculation method it was produced with, so it can be checked later.

Known limits

  • Dates are projections until a sighting confirms them.
  • City coordinates are a single representative point; a large metropolitan area has real variation across it, usually under a minute or two.
  • Elevation and local horizon obstruction are not modelled in detail.
  • High-latitude locations need a convention for months when the sun does not reach the required angle, and any such convention is a choice rather than a computation.

If you find a time that looks wrong for your city, please tell us on the Corrections page.