13.3% of the 120-year cycle, divided into nine antardashas. Every length here is 16 × B / 120 — arithmetic, not opinion.
Jupiter Mahadasha runs for 16 years, which is 13.3% of the 120-year cycle. It follows Rahu Mahadasha (18 years) and is followed by Saturn Mahadasha (19 years). Because the cycle is 120 years long and a life is not, most people meet it once or not at all — when it arrives depends entirely on where in the sequence you were born.
You are born into it if the Moon was in Punarvasu, Vishakha, Purva Bhadrapada — the three nakshatras Jupiter rules.
Every mahadasha is divided into nine sub-periods in the same order, starting with its own lord. An antardasha of B inside Jupiter runs for 16 × B / 120 years — so the longest here is Jupiter–Venus and the shortest is Jupiter–Sun. The nine add to 5,844 days, which is the mahadasha’s own rounded length — they divide it with nothing left over and nothing borrowed.
| Antardasha | Length | In days |
|---|---|---|
| Jupiter–Jupiter | 2y 1m 18d | 779 days |
| Jupiter–Saturn | 2y 6m 12d | 925 days |
| Jupiter–Mercury | 2y 3m 6d | 828 days |
| Jupiter–Ketu | 11m 6d | 341 days |
| Jupiter–Venus | 2y 8m 0d | 974 days |
| Jupiter–Sun | 9m 18d | 292 days |
| Jupiter–Moon | 1y 4m 0d | 487 days |
| Jupiter–Mars | 11m 6d | 341 days |
| Jupiter–Rahu | 2y 4m 25d | 877 days |
A DASHA YEAR HERE IS 365.25 DAYS, which is what the chart engine uses. It is the common modern convention and it is not the only one — software set to a 360-day savana year makes this mahadasha 5,760 days instead of 5,844, a difference of 84. So these figures match a panchang using the same year length, and will differ from one that does not. The ratio between the nine sub-periods is the same either way.
Classical jyotisha associates Jupiter with teachers, children, belief, expansion and good counsel. That is the tradition’s reading and it is offered as such: everything above this line is arithmetic, and this line is not. What a period does in a particular life depends on where Jupiter actually sits in that chart — which house it rules, which it occupies, and what aspects it. A page cannot know that; a chart can.
16 years, which is 13.3% of the 120-year Vimshottari cycle. It is divided into nine antardashas, the longest being Jupiter–Venus.
It runs from birth if the Moon was in Punarvasu, Vishakha, Purva Bhadrapada — the nakshatras Jupiter rules. Otherwise it arrives in sequence after Rahu Mahadasha, and whether it arrives in your lifetime depends on where in the cycle you were born.
Nine, in the fixed order starting with Jupiter itself. Each runs for 16 x its own dasha years / 120 — for example Jupiter–Jupiter is 2y 1m 18d. The nine together come to exactly 16 years.
It follows from the Moon’s nakshatra at your birth. Cast the chart free and the whole 120-year timeline comes with it.