Your Vimshottari dasha timeline

What this computes

Vimshottari is a cycle of a hundred and twenty years, divided into nine unequal periods, one ruled by each graha. Which period you were born into is decided by the nakshatra your Moon occupied, since each of the twenty-seven nakshatras belongs to one of the nine rulers. How much of that first period was left at birth is decided by how far through the nakshatra the Moon had already travelled: a Moon a quarter of the way through a nakshatra begins life with three quarters of that ruler’s period remaining.

From that single starting balance everything else follows by proportion. This page computes the major periods, the sub-periods within them, and the sub-periods within those, and marks the one running now.

The convention that shifts every date

A dasha length is quoted in years, and there is more than one year in use. Some practice counts a year as three hundred and sixty days, following the savana convention; other practice uses the solar year of about three hundred and sixty-five and a quarter days. The difference is small per year and compounds over a hundred and twenty, which is why two correctly computed timelines for the same birth can put a period change months or years apart.

Before comparing two dasha timelines, check that they used the same length of year and the same ayanamsa — otherwise you are comparing two different measuring sticks.

Birth time matters here too. The Moon moves about half a degree an hour, so an hour of error is a small fraction of a nakshatra — but that fraction is being scaled up to as much as twenty years, and it moves the boundaries by months rather than days. The Moon’s position can be checked against JPL. Our sampled Sun-through-Saturn validation measured a maximum difference of 0.44 arc-seconds. This does not verify the birth record or the convention used to convert a dasha year into calendar dates.

What the result does and does not mean

A dasha period is a name attached to a span of time by one system of reckoning. This page tells you which name applies to which years. It does not tell you what will happen in those years, and we do not write that anywhere on this site.

Vimshottari is one dasha system among several. Ashtottari, Yogini and Kalachakra exist, run on different lengths, and are used in different regions. Vimshottari is the most widely applied and is the one usually meant when a period is quoted without qualification — but a timeline is always a timeline according to a named system.

Why does my current period differ from what I was told?

Three candidates, in order of likelihood: a different year-length convention, a different ayanamsa moving the Moon across a nakshatra boundary, and a different birth time. If the nakshatra itself differs, the whole timeline differs; if only the dates differ, it is one of the first two.

What is an antardasha?

The sub-period inside a major period, sharing out that period among all nine rulers in the same proportions as the full cycle. A third level, the pratyantardasha, divides each sub-period again. Each level is arithmetic on the level above it, so an error at the top carries all the way down.

Is a dasha relevant to a matching decision?

Some traditions consult it when a family asks about timing, and some do not consult it for compatibility at all. If a refusal you were given rested on a period, the useful question is which text supports treating that period that way.