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Tahajjud Time | Find Last Third of Night From Sunset and 18° Dawn

Calculates the last third of the night — the most virtuous tahajjud window — from your sunset and 18°-dawn times for any latitude, longitude and date.

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

e.g. −5 New York (EST), 0 London (GMT), +3 Makkah, +5.5 India. Use your current DST offset.

North positive, south negative (e.g. 40.71 for NYC, 21.42 for Makkah).

East positive, west negative.

Results

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

The most virtuous hours for tahajjud are the last third of the night, when the Prophet ﷺ said Allah descends to the lowest heaven asking: “Who calls on Me, that I may answer him?” (Bukhari 1145). Finding that window means knowing two times precisely — maghrib, when the Islamic night begins, and fajr at 18° sun depression, when it ends. This calculator computes both with NOAA solar equations for any latitude, longitude and date, then splits the night into halves and thirds.

Enter tonight’s date and your coordinates: you get maghrib, the midpoint, the moment the last third begins, true dawn and sunrise — so you can set an alarm for the exact window rather than guessing. High-latitude summers where 18° dawn never occurs are detected automatically and handled with a sunrise fallback and a note to follow your local timetable.

From our guides

Quick reference

City (21 Jun 2026)MaghribFajr (18°)Last third begins
New York (40.71, −74.01, UTC−4)8:31 PM3:19 AM1:03 AM
London (51.51, −0.13, UTC+1)9:22 PM— (persistent twilight)sunrise-based
Makkah (21.42, 39.83, UTC+3)7:05 PM~4:05 AM~1:05 AM
Kuala Lumpur (3.14, 101.69, UTC+8)7:26 PM~5:30 AM~2:10 AM

info Tahajjud Time Calculator

Free islamic calculator — enter your numbers and get an instant, accurate result.

info Private by design

Everything runs locally in your browser. No uploads, no accounts, no tracking.

info Works everywhere

Fully responsive and mobile-friendly — calculate on any device, any time.

info Educational

Includes the formula and step-by-step explanation so you understand the math, not just the answer.

Interpretation guide

WindowVirtue
Any time after IshaTahajjud/qiyam is valid all night
After the midpointGreater reward — the night's depth begins
Last thirdMost virtuous: Allah descends to the lowest heaven and answers supplication (Bukhari 1145)
After 18° fajrNight prayer window has closed — pray Fajr

lightbulb Worked example

Let's say you are using the Tahajjud Time Calculator. Calculates the last third of the night — the most virtuous tahajjud window — from your sunset and 18°-dawn times for any latitude, longitude and date. Enter the values that match your situation into the input fields and press calculate — using realistic numbers makes the result directly useful for you.

Result: The calculator instantly applies the formula Night = maghrib → fajr (18° dawn); last third begins = maghrib + 2⁄3 × night length and returns the result with appropriate precision.

What this means: Read the result in the context of what you are measuring. The step-by-step breakdown lets you confirm the math and understand which input most affects the outcome.

Formula & methodology

Formula: Night = maghrib → fajr (18° dawn); last third begins = maghrib + 2⁄3 × night length

The Tahajjud Time Calculator is built on a well-established calculation method. It uses the formula Night = maghrib → fajr (18° dawn); last third begins = maghrib + 2⁄3 × night length to turn your inputs into a reliable result. Calculates the last third of the night — the most virtuous tahajjud window — from your sunset and 18°-dawn times for any latitude, longitude and date. The steps are shown on the page so you can follow the reasoning from input to output.

  1. Pick the evening date — the night runs from that day's sunset to the next morning's dawn.
  2. Enter latitude, longitude and your current UTC offset (including DST).
  3. The calculator computes maghrib (sunset, 90.833° zenith) and fajr (sun 18° below the horizon) with NOAA solar equations.
  4. The night is split into thirds: the last third begins at maghrib + 2⁄3 of the night's length.

Worked example: New York on 21 June 2026 — maghrib 8:31 PM, fajr 3:19 AM, night length 6h 48m, midpoint 11:55 PM, so the last third begins at 1:03 AM.

Authoritative source: Islamic Relief

Frequently asked questions

What time is tahajjud?
Tahajjud can be prayed any time between Isha and Fajr, but the most virtuous window is the last third of the night. Enter your location and the calculator returns tonight's exact window — for New York on 21 June 2026 it begins at 1:03 AM.
How is the last third of the night calculated?
The Islamic night runs from maghrib (sunset) to fajr (true dawn, sun 18° below the horizon). Divide that span by three and add two-thirds to the maghrib time: a 6h 48m night starting 8:31 PM puts the last third at 1:03 AM.
Why is the last third of the night special?
The Prophet ﷺ said our Lord descends to the lowest heaven in the last third of every night, saying: “Who calls on Me, that I may answer him?” (Bukhari 1145, Muslim 758). It is the prime time for duʻa and istighfar.
Do I have to sleep before praying tahajjud?
Most scholars define tahajjud as night prayer after some sleep, while qiyam al-layl is any night prayer. If you stay up, you still earn the reward of qiyam — but the sunnah is to sleep, then rise.
What if dawn never reaches 18° at my latitude in summer?
Above ~48° latitude in midsummer, twilight can persist all night. The calculator then falls back to sunrise as the night's end and tells you — in practice, follow your local mosque timetable, which applies a high-latitude convention (nearest day, 1/7 of night, or aqrab al-bilad).
What does the Tahajjud Time Calculator do?
Calculates the last third of the night — the most virtuous tahajjud window — from your sunset and 18°-dawn times for any latitude, longitude and date. The calculator takes your inputs, applies the standard calculation, and returns a clear result so you can make an informed decision without doing the math by hand.
What formula does the Tahajjud Time Calculator use?
It defines the night as the interval from Maghrib to Fajr (18° dawn) and computes the last third as last-third start = Maghrib + 2⁄3 × night length. Enter your sunset and dawn times, or location and date, and the tool returns when the final third begins and ends. Tahajjud may be prayed any time after Isha, but the last third is considered the most virtuous.
Is the Tahajjud Time Calculator free and private?
Yes — the Tahajjud Time Calculator. There is no sign-up, no paywall, no trial, and no limit on how many calculations you can run. CalcaTools covers its costs with non-intrusive display advertising, so the calculator itself never asks for payment or restricts any feature.
How accurate is the Tahajjud Time Calculator?
The Tahajjud Time Calculator applies the standard formula: Night = maghrib → fajr (18° dawn); last third begins = maghrib + 2⁄3 × night length. It is tested against published worked examples before launch and uses native double-precision arithmetic, so results are accurate to typical precision for the values you enter — with no intermediate rounding that could distort the answer.

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