Rāhu Kālam, Yamagaṇḍam, Guḷika and Durmuhūrtam

How they are derived

The daytime — sunrise to sunset — is divided into eight equal parts. Which part is Rāhu Kālam depends on the weekday, and the same is true of Yamagaṇḍam and Guḷika Kālam, each with its own weekday assignment.

Because the parts are eighths of a variable daylight, their length changes through the year: about ninety minutes at midsummer in the Bay Area and about seventy at midwinter. Any table of fixed clock times is a table for somewhere else.

Durmuhūrtam is derived differently: the daytime is divided into fifteen muhūrtas, and one or two of them are set aside according to the weekday.

Guḷika Kālam in Sri Kumar Gurukkal’s tradition

This is where traditions genuinely differ, and this site follows Gurukkal rather than the general run of almanacs.

In his tradition and practice, Guḷika Kālam is not a general restriction on ordinary poojas and ceremonies. Certain death-related rites should not be begun during it. For anything else, the priest responsible for the rite gives the final guidance.

That is why this site shows Guḷika as context-dependent rather than as a prohibition, and why the daily panel labels it differently from Rāhu Kālam and Yamagaṇḍam.

What they are not

They are not a forecast of misfortune, and treating them as one leads people into a kind of anxious clock-watching that the tradition does not ask for. The consistent traditional framing is narrower: these are periods in which an auspicious undertaking is not begun.

Travel, work, meals and everything else ordinary continue. A pooja already in progress continues. A rite that has to happen — a birth, a bereavement — happens.

What a family may do

• Check the day’s Rāhu Kālam before fixing the hour of a housewarming or a shop opening, not before every errand.
• Remember they are local. Use times computed for where the ceremony will be.
• If a period falls awkwardly across the only hour a family can gather, say so to Gurukkal rather than assuming the date is lost.

Often misunderstood

• That Rāhu Kālam is a fixed time like 4:30 to 6:00. It is an eighth of the daylight and moves through the year.
• That something bad happens during it. The tradition speaks about beginnings.
• That Guḷika Kālam bars ordinary poojas. In this tradition it does not.

Where traditions differ

• The weekday assignment of the eight parts is consistent across most published almanacs. The treatment of Guḷika, and the number of Durmuhūrtam periods on a Saturday, are two places where sources differ — this site’s Saturday value is recorded as an owner decision awaiting Gurukkal’s review, and says so in its own ruleset.

Explaining it to a child

Every day has a stretch of time when grown-ups prefer not to start something new — a bit like not starting a long car journey right at bedtime. It moves around depending on the day of the week and how long the day is.