Rahu kaal (also written Rahu kalam, Rahu kalaya or Rahukalam) is a stretch of about an hour and a half each day that Hindu tradition regards as a poor time to begin something new. It is named for Rahu, the shadow planet of Vedic astrology, and it is observed most strongly in South India, though many families across India and abroad check it before a journey, a purchase or the start of a puja. Astrologers differ on how strictly it should be followed, and work that is already under way is generally left to carry on.
How Rahu kaal is calculated
The rule uses only the length of the day and the weekday. Take the time from sunrise to sunset in your own city and divide it into eight equal parts. A day of 12 hours from 6 am to 6 pm gives eight parts of 90 minutes, and a longer or shorter day gives longer or shorter parts. Each weekday then has its own part that is Rahu kaal:
| Weekday | Part of the day that is Rahu kaal | Yamaganda | Gulika kaal |
|---|---|---|---|
| Sunday | 8th | 5th | 7th |
| Monday | 2nd | 4th | 6th |
| Tuesday | 7th | 3rd | 5th |
| Wednesday | 5th | 2nd | 4th |
| Thursday | 6th | 1st | 3rd |
| Friday | 4th | 7th | 2nd |
| Saturday | 3rd | 6th | 1st |
As a worked example, on a Monday with sunrise at 6 am and sunset at 6 pm the second part runs from 7:30 am to 9:00 am, so that is Rahu kaal. On a Saturday under the same sunrise and sunset the third part gives 9:00 am to 10:30 am. In summer, when the day is long, the parts are longer than 90 minutes, and in winter they are shorter. Near the poles, where the Sun may not rise or set at all, the rule cannot be applied.
Because the parts are counted from the local sunrise, Rahu kaal is a different clock time in every city, and it moves a little from one day to the next as sunrise moves. Use the table below or the page of your own city on the panchang hub rather than a time copied from another place.
Yamaganda and Gulika kaal
Two more periods are worked out in the same way and are often listed beside Rahu kaal. Yamaganda is named for Yama, the lord of death, and Gulika kaal for Gulika, a son of Saturn in the astrological tradition. Both are read as unfavourable for fresh beginnings. Almanacs and families vary in how much weight they give to each of the three, and none of these periods is a prediction about what will happen.
What the tradition says to do
Many people simply avoid starting a journey, signing a document, beginning a new venture, or opening a puja during Rahu kaal, and choose the time just before or after it instead. Daily routines, work already in progress, and prayer or meditation as such are not affected. The calculation is not an instruction to be afraid of a time of day. If your family or your temple’s printed almanac keeps a different custom, follow it.
For a fuller choice of timings use choghadiya and hora, which divide the same day into favourable and unfavourable slots, or look up the day’s tithi and nakshatra on your city’s page. For the dates of festivals see the festivals pages.