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Ramadan Fasting Hours Calculator | Fajr to Maghrib

A Ramadan fasting hours calculator computes the daily fast duration between Fajr (dawn) and Maghrib (sunset) for your latitude and longitude during a chosen Ramadan, using selectable calculation methods (MWL, ISNA, Egypt, Makkah, Karachi). It samples days 1, 6, 11, 16, 21 and 26 so you see how fast length drifts through the month.

Last updated: September 2026 · Free · No sign-up required

Tool predicts the Gregorian dates of 1 Ramadan and 29/30 Ramadan automatically.

Results

Enter values above and click Calculate to see your result instantly.

Quick reference

Approximate first-day fast lengths, Ramadan 1447:

CityFajrMaghribFast
Makkah05:2118:1312 h 52 m
London05:0417:3312 h 29 m
New York05:2417:4512 h 21 m
Karachi05:4618:1912 h 33 m

public Latitude effect

Every 10° of latitude away from the equator adds seasonal swing — mid-Ramadan drift can exceed 2 hours in northern Europe.

schedule The 11-day shift

Ramadan starts ~11 Gregorian days earlier each year, so fast lengths in the same city cycle through all four seasons over 33 years.

tune Method matters

ISNA's 15° Fajr starts fasts ~20 min later than MWL's 18° — follow your community's established convention.

water_drop Suhoor timing

Plan suhoor to end at the printed Fajr, not '10 minutes before' — the fast begins at first true dawn.

lightbulb A real example — London, Ramadan 1447

London (51.5°N), MWL method, first day of Ramadan 1447.

Result: Fast ≈ 12 h 29 m (Fajr ~05:04, Maghrib ~17:33), lengthening to about 13 h 15 m by day 26.

What this means: Because Ramadan 1447 sits near the equinox, London's fasts are mild — a striking contrast to the ~19 h fasts of the June Ramadans of the 2010s.

Formula & methodology

Formula: Fast hours = Maghrib − Fajr (solar depression angles: Fajr −18°/−15°/−19.5° by method; Maghrib = sunset + 1 min)

How fast length is computed

Fasting runs from Fajr (true dawn, when the sun reaches a set angle below the horizon) to Maghrib (sunset). Prayer-time algorithms solve the sun's depression angle for your coordinates:

  • MWL: Fajr at 18°, Maghrib at sunset
  • ISNA: Fajr at 15°
  • Egyptian General Authority: Fajr at 19.5°
  • Umm al-Qura (Makkah): Fajr at 18.5°, Maghrib +90 min (EPT)

Higher latitude and mid-summer Ramadan stretch fasts toward 18–20+ hours in northern Europe, while equatorial fasts stay near 13 hours year-round. The calculator samples six days across Ramadan 1447 (expected ≈ 18 Feb – 19 Mar 2026) to show the drift.

Authoritative source: PrayTimes.org

Frequently asked questions

How many hours is a Ramadan fast?
Between Fajr and Maghrib — roughly 12–14 hours for most of the world's Muslims, stretching past 18 hours at high latitudes in summer Ramadans.
What time does the fast start and end?
It starts at Fajr (true dawn, before sunrise) and ends at Maghrib (sunset). Exact clock times depend on your coordinates and calculation method.
Why do fasting hours differ between countries?
Day length varies with latitude and season. Two cities on the same day can differ by 4+ hours; the same city differs across the month as Ramadan drifts.
Which prayer-time method should I follow?
Follow your local mosque's convention: MWL in Europe, ISNA in North America, Egyptian authority in Africa/Levant, Umm al-Qura in Saudi Arabia.

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