What it is. Rahu Kaal is one of the eight equal parts the daylight is divided into, from sunrise to sunset. Which part it is depends on the weekday, and that is fixed by convention rather than read from the sky. Its length, though, is simply the daylight divided by eight — so it is as long as the day is.
Where ninety minutes comes from. Twelve hours of daylight, divided by eight, is ninety minutes exactly. That is the whole of it. The figure is not folklore and it is not a rounding — it is the right answer for a twelve-hour day. The question this post answers is how often a day is twelve hours long.
How long is Rahu Kaal, really?
Between 44 minutes and 142, depending on where you are and what the date is. Across 27,825 place-days, 30.8% came within five minutes of ninety and 46.1% were shorter than ninety. So ninety is a fair middle. It is not the answer on most days.
Ninety minutes is right for a twelve-hour day. 30.8% of days are close to one.
A spread of the measured lengths in five-minute bands. The commonest band is 90 to 95 minutes at 16.4% of place-days, and the tails reach from 44 minutes to 142.Each bar is a five-minute band, labelled by its lower edge in minutes. The peak sits over ninety, which is why the nominal figure survives — it is never far wrong, and rarely exactly right.
How long is Rahu Kaal in India?
From 74.1 minutes to 108.2 across the 171 Indian cities with a page here. Both ends are Srinagar, in December and in June. In Delhi it runs 77.4 to 104.8 minutes — 1h 17m to 1h 45m — a swing of 27.4 minutes across the year.
| City | Shortest | Longest | Spread |
|---|---|---|---|
| Srinagar | 74.1 min | 108.2 min | 34.1 min |
| Delhi | 77.4 min | 104.8 min | 27.4 min |
| Ahmedabad | 80.4 min | 101.6 min | 21.2 min |
| Kolkata | 80.7 min | 101.4 min | 20.7 min |
| Mumbai | 82.4 min | 99.6 min | 17.2 min |
| Bengaluru | 85.2 min | 96.7 min | 11.5 min |
| Chennai | 85.2 min | 96.7 min | 11.5 min |
| Thiruvananthapuram | 87.2 min | 94.6 min | 7.4 min |
Ordered by latitude, and the spread column follows it down. Bengaluru and Chennai match to the minute because they sit at the same latitude — which is the whole mechanism in one row.
Why does the length change at all?
Because daylight does. The further you are from the equator, the more the day stretches in summer and shrinks in winter, and an eighth of it stretches and shrinks with it. Srinagar swings 34.1 minutes across the year; Thiruvananthapuram, much nearer the equator, swings 7.4.
The control case is the equator itself. At Entebbe the day barely changes length, so it sits between 90.8 and 90.9 minutes all year — a spread of 0.1 minutes. At the other end, Helsinki runs from 43.6 minutes in winter to 142 in summer.
It is also why a clock cannot help you. The Rahu Kaal page works the span out from sunrise and sunset at your own place for the day you ask about, and every city page does the same for one place.
Questions people ask about Rahu Kaal timing
Is Rahu Kaal always 90 minutes?
No. It is an eighth of the daylight, so ninety minutes is only right when the day is exactly twelve hours long. Measured over 27,825 place-days, 30.8% came within five minutes of ninety and the rest did not.
How long is Rahu Kaal today in Delhi?
Between 77.4 and 104.8 minutes depending on the date — 1h 17m around the winter solstice, 1h 45m around the summer one. The exact span for today is on the Delhi Rahu Kaal page, worked out from that day's sunrise and sunset.
Why do two websites show different Rahu Kaal timings?
Usually because they resolved the place differently. Sunrise moves with longitude and latitude, so a site using a state capital where you wanted a nearby town will shift both the start and the length. A fixed ninety-minute block will also disagree with a computed one on most days.
Which part of the day is Rahu Kaal?
It depends on the weekday, and the mapping is a convention rather than a measurement: the eighth part on Monday, the seventh on Saturday, and so on. The engine applies the standard table. What it computes from the sky is where the eight parts fall, not which of them carries the name.
Does Rahu Kaal apply at night?
Not in the usual reckoning. The eight parts are divisions of the daylight, from sunrise to sunset, so the span ends at sunset. The night is divided separately for Choghadiya, and that is a different set of names.
Is Rahu Kaal longer in summer?
Yes, everywhere away from the equator, because the daylight it divides is longer. In Srinagar the summer span is 34.1 minutes longer than the winter one; near the equator the difference nearly vanishes.
What is the shortest Rahu Kaal possible?
Among the places measured here, 43.6 minutes at Helsinki in midwinter. Further north it keeps shrinking, and above the Arctic circle there are days with no sunrise at all, where the division has nothing to divide.
What this does not cover
- Which eighth is Rahu Kaal is a convention, not a measurement. The weekday table is near-universal and it is still a table. What this engine computes is where the eight parts fall; the naming is applied on top.
- Sunrise here is the standard one — the Sun's upper limb at the horizon, with atmospheric refraction. That is why even an equatorial day runs a few minutes past twelve hours, and why its Rahu Kaal is near 91 minutes rather than exactly 90.
- Local horizon is not modelled. A hill or a high building to the east delays the sunrise you can actually see. The figures assume a level horizon, as every published panchang does.
- A seven-day sample, not every day. Daylight moves slowly and smoothly, so the shape is the same either way; the yearly extremes are read off the solstices rather than sampled, so those are exact.
- Nothing here says what to do with the time. The tradition marks the span; it does not tell you what will happen in it, and this post makes no claim about that either.