What is a dasha?
A dasha is a planetary period. Vedic astrology holds that a chart does not deliver everything at once — each graha gets its turn to rule a stretch of the life, and what it delivers during that stretch depends on how well placed it is in your chart.
The system in near-universal use is Vimshottari, which divides 120 years among the nine grahas in a fixed order and fixed proportions:
- Ketu — 7 years
- Venus — 20 years
- Sun — 6 years
- Moon — 10 years
- Mars — 7 years
- Rahu — 18 years
- Jupiter — 16 years
- Saturn — 19 years
- Mercury — 17 years
They always run in that order and always total 120. What differs between people is where in the cycle you start, and how much of your first period was left when you were born.
How your starting point is decided
Entirely by the Moon.
Each of the 27 nakshatras is ruled by one of the nine grahas, cycling in the Vimshottari order. Whichever star the Moon occupied at your birth, its ruler supplies your first mahadasha.
How much of it you got is set by how far through that star the Moon had travelled. Born with the Moon 60% of the way through a Venus star, you begin life with 40% of the 20-year Venus mahadasha remaining — eight years. Every date in your dasha map, for the next century, follows from that one figure.
This is why the birth time matters so much here. The Moon covers about 13 degrees a day, so a few hours' error shifts the balance by months, and a birth near a nakshatra boundary can change the starting planet altogether — which reorders the entire sequence.
Mahadasha, antardasha, pratyantardasha
Each mahadasha subdivides into nine antardashas in the same order and the same proportions, and each antardasha into nine pratyantardashas. The nesting can continue further; three levels is what practising astrologers normally use.
The reading works in layers. The mahadasha sets the chapter — a nineteen-year Saturn period is a different decade or two from a sixteen-year Jupiter one. The antardasha sets the scene inside it, which is why a difficult mahadasha still has good years and a benefic one still has bad months. The pratyantardasha narrows to weeks.
One structural detail worth knowing: the first antardasha of any mahadasha is always ruled by the mahadasha lord itself. That is why the opening stretch of a period feels most purely characteristic of it.
A dasha is only as good as its planet
The single biggest error people make with dasha readings is treating the period as though the planet were generic. It is not.
A Jupiter mahadasha with Jupiter exalted in the 9th is a fortunate sixteen years. The same mahadasha with Jupiter debilitated in the 8th and combust is not, and no amount of general text about Jupiter's benevolence will make it so.
That is why this calculator prints where each dasha lord sits in your chart — sign, house and dignity — next to every period, rather than handing you nine paragraphs that would be identical for everyone.
The 365.25-day year
Dasha dates disagree between sources more often than they should, and the usual reason is the length of the year.
The classical Vimshottari year is the Julian year of 365.25 days, which is traditional Indian practice uses. The Gregorian 365.2425 is sometimes used instead. The difference is small per year and accumulates to several months across a 120-year cycle — enough to move a mahadasha boundary past a real event. We use 365.25, and say so.
Frequently asked questions
What is a mahadasha?
The main planetary period in the Vimshottari system, ruled by one graha and lasting between 6 and 20 years. The nine mahadashas together cover 120 years.
How do I know which dasha I am running?
Enter your birth details above. The calculator computes your position in the cycle and shows the mahadasha, antardasha and pratyantardasha running today, with how long each has left.
Why does my dasha differ from another website?
Two common causes. Either the site used a different year length — the classical value is 365.25 days, and some use 365.2425 — or your birth time produced a different Moon position and therefore a different starting nakshatra.
Do I need my exact birth time?
Yes — more than any other reading here. Your entire dasha sequence is set by how far the Moon had travelled through its nakshatra, and the Moon moves about 13 degrees a day.
Is a Saturn mahadasha always bad?
No. Saturn's nineteen years bring delay, responsibility and slow progress, which is hard — but it is also the period in which durable things get built. A well-placed Saturn delivers real, lasting gain. Its position in your chart decides which you get.
What is the balance of dasha at birth?
The portion of your first mahadasha that remained when you were born, set by how far through its nakshatra the Moon had travelled. Every subsequent date follows from it.
