Vimshottari dasha divides a 120-year cycle among nine planets, and the Moon’s nakshatra at birth decides where in that cycle you start. Enter a birth date, time and time zone above and the calculator gives the balance of dasha at birth, all nine mahadashas, the antardashas inside each one and the pratyantardashas running now, dated in your own zone.
It also tells you something most dasha tables leave out: how far the dates move if the birth time is a few minutes off. For a Venus or Saturn nakshatra the answer is close to five days per minute, which is the single best reason to dig out the birth certificate before reading anything into a dasha change.
What is Vimshottari dasha?
Vimshottari means one hundred and twenty. The system gives each of nine grahas a fixed number of years, always in the same order: Ketu 7, Venus 20, Sun 6, Moon 10, Mars 7, Rahu 18, Jupiter 16, Saturn 19 and Mercury 17, which sum to 120. Each planet also rules three nakshatras, one in every third of the zodiac, so the nakshatra the Moon occupied at birth hands you your first planet. From there the periods simply run on in order and wrap round: a Rahu start goes on to Jupiter, Saturn, Mercury, Ketu and so on.
| Planet | Mahadasha years | Nakshatras it rules | Share of 120 years |
|---|---|---|---|
| Ketu | 7 | Ashwini, Magha, Mula | 5.8% |
| Venus | 20 | Bharani, Purva Phalguni, Purva Ashadha | 16.7% |
| Sun | 6 | Krittika, Uttara Phalguni, Uttara Ashadha | 5.0% |
| Moon | 10 | Rohini, Hasta, Shravana | 8.3% |
| Mars | 7 | Mrigashira, Chitra, Dhanishta | 5.8% |
| Rahu | 18 | Ardra, Swati, Shatabhisha | 15.0% |
| Jupiter | 16 | Punarvasu, Vishakha, Purva Bhadrapada | 13.3% |
| Saturn | 19 | Pushya, Anuradha, Uttara Bhadrapada | 15.8% |
| Mercury | 17 | Ashlesha, Jyeshtha, Revati | 14.2% |
Order and years as given in the Wikipedia article on dasha, which quotes Phala Dipika; nakshatra lords from the List of Nakshatras. Both checked October 2026. Source: saturnreturn-calculator.com
Nobody lives through all nine in full. You are born partway through the first one, and the cycle that started before your birth ends 120 years after its notional start, so the timeline above lists your first mahadasha from birth and the rest in full.
How the balance of dasha at birth is worked out
The rule is a straight proportion. Take the Moon’s sidereal longitude at birth, find how far it has travelled through its 13°20′ nakshatra, and treat the part still to come as the part of the ruling planet’s dasha still to run. A Moon 40% of the way through a Rahu nakshatra leaves 60% of Rahu’s 18 years, which is 10.8 years. Every later date is that balance plus whole periods added end to end.
Worked example: 27 April 1993, 06:40 IST
For a birth at 06:40 in UTC+5:30 on 27 April 1993, the calculator puts the Moon at 11°55′ of Mithuna, in Ardra pada 2. Ardra is ruled by Rahu, and the Moon had covered 39.4% of it, so 10 years, 10 months and 29 days of Rahu remained, running to 26 March 2004. Jupiter followed until 26 March 2020, and Saturn’s 19 years run from then to 27 March 2039. In October 2026 this person is in Saturn mahadasha, Ketu antardasha (7 December 2025 to 16 January 2027), with Venus antardasha next and lasting until 17 March 2030. Shift the birth time five minutes later and every one of those dates comes about 22 days earlier.
Mahadasha, antardasha and pratyantardasha
Each mahadasha splits into nine antardashas, also called bhuktis, in the same planetary order but starting from the mahadasha’s own planet. The length of each is the mahadasha years times the antardasha planet’s years, divided by 120. Inside Saturn’s 19 years, Mercury’s bhukti is 19 × 17 ÷ 120 = 2.69 years, or 2 years, 8 months and 9 days. Antardashas split again into pratyantardashas by exactly the same rule, which is why the calculator shows them only for the period you are in: Sun within Sun within Sun lasts about five and a half days.
The grid below gives every antardasha length. Read across the row of your mahadasha; the periods run in order starting from the bold cell, then continue left to right and wrap round to Ketu.
| Mahadasha | Ketu | Venus | Sun | Moon | Mars | Rahu | Jupiter | Saturn | Mercury |
|---|---|---|---|---|---|---|---|---|---|
| Ketu | 4m 27d | 1y 2m | 4m 6d | 7m | 4m 27d | 1y 18d | 11m 6d | 1y 1m 9d | 11m 27d |
| Venus | 1y 2m | 3y 4m | 1y | 1y 8m | 1y 2m | 3y | 2y 8m | 3y 2m | 2y 10m |
| Sun | 4m 6d | 1y | 3m 18d | 6m | 4m 6d | 10m 24d | 9m 18d | 11m 12d | 10m 6d |
| Moon | 7m | 1y 8m | 6m | 10m | 7m | 1y 6m | 1y 4m | 1y 7m | 1y 5m |
| Mars | 4m 27d | 1y 2m | 4m 6d | 7m | 4m 27d | 1y 18d | 11m 6d | 1y 1m 9d | 11m 27d |
| Rahu | 1y 18d | 3y | 10m 24d | 1y 6m | 1y 18d | 2y 8m 12d | 2y 4m 24d | 2y 10m 6d | 2y 6m 18d |
| Jupiter | 11m 6d | 2y 8m | 9m 18d | 1y 4m | 11m 6d | 2y 4m 24d | 2y 1m 18d | 2y 6m 12d | 2y 3m 6d |
| Saturn | 1y 1m 9d | 3y 2m | 11m 12d | 1y 7m | 1y 1m 9d | 2y 10m 6d | 2y 6m 12d | 3y 3d | 2y 8m 9d |
| Mercury | 11m 27d | 2y 10m | 10m 6d | 1y 5m | 11m 27d | 2y 6m 18d | 2y 3m 6d | 2y 8m 9d | 2y 4m 27d |
y = years, m = months, d = days, with 365.25-day years split into twelve equal months. Each cell is mahadasha years × antardasha years ÷ 120. Source: saturnreturn-calculator.com
Why your birth time matters more here than anywhere else
The Moon moves about half a degree an hour, which barely matters for a 30° rashi but matters a great deal for the dasha balance, because the whole of a planet’s period is mapped onto a 13°20′ nakshatra. At the Moon’s average speed, one minute of birth time moves every dasha date by 1.5 days in a Sun nakshatra, 1.75 days for Ketu or Mars, 2.5 days for the Moon, 4 days for Jupiter, 4.3 days for Mercury, 4.5 days for Rahu, 4.8 days for Saturn and 5 days for Venus. The Moon runs up to 17% faster or 11% slower than average, and the calculator uses its real speed at your birth when it prints the figure under your results.
That has a plain consequence. A birth time written as 10:30 when the baby actually arrived at 10:22 shifts a Venus-born chart by about 40 days. If your recorded time is rounded to the quarter hour, treat every date in the table as a window of several weeks, not a day. Rectification by an astrologer, working back from dated life events, is the traditional fix when the time is doubtful.
Why dasha calculators disagree
- Year length. This calculator counts a dasha year as 365.25 days, the solar year the Wikipedia article on dasha gives and the length most dasha software uses by default. Some astrologers prefer a 360-day savana year, which ends a 19-year Saturn mahadasha about 100 days sooner (19 × 5.25 days) and moves dates late in life by more than a year.
- Ayanamsa. The dasha balance follows the sidereal Moon, so the ayanamsa feeds straight into it. Raman sits about 1°27′ from Lahiri in 2026, which is 11% of a nakshatra and can move a Venus dasha boundary by over two years. KP differs from Lahiri by under 6 arcminutes, which is under two months even for Venus.
- Time zone and summer time. One hour of zone error moves the Moon half a degree, which at five days per minute is up to ten months of dasha error.
- The Moon itself. Each arcsecond of lunar error is worth about three and a half hours of dasha in a Venus chart. The engine here keeps 60 terms of lunar theory; on 500 random births from 1930 to 2025, its 45,000 period start dates came within two-thirds of a day of an independent Swiss Ephemeris calculation for 95% of them, and within 1.3 days at worst.
Saturn mahadasha is not Sade Sati
The two are often confused, and this site deals in both. Saturn mahadasha is a 19-year span of your personal Vimshottari timeline, fixed at birth by the nakshatra of your Moon; anyone born in Pushya, Anuradha or Uttara Bhadrapada begins life in it. Sade Sati is a transit, about seven and a half years when Saturn passes through the twelfth, first and second rashis from your Moon, and it comes round roughly every 30 years for everybody. The two can overlap or not, and the worked example above shows both at once: that chart’s Saturn mahadasha runs from 26 March 2020 to 27 March 2039, while Sade Sati for its Mithuna Moon runs from 8 August 2029 to 27 August 2036, wholly inside it. Saturn mahadasha comes at most once in a lifetime; Sade Sati usually comes two or three times. To see your transit dates, use the Sade Sati calculator; for your nakshatra, pada and the exact times the Moon entered and left it, use the nakshatra calculator.
Frequently Asked Questions
What is Vimshottari dasha?
Vimshottari dasha is the Vedic system of planetary periods keyed to the Moon at birth. It divides a 120-year cycle among nine planets in a fixed order: Ketu 7 years, Venus 20, Sun 6, Moon 10, Mars 7, Rahu 18, Jupiter 16, Saturn 19 and Mercury 17. The nakshatra the Moon occupied at birth sets which planet's period you were born into and how much of it remained. Each mahadasha then divides into nine antardashas in the same order.
How is the balance of dasha at birth calculated?
Find the Moon's sidereal longitude at birth, work out what fraction of its 13 degree 20 minute nakshatra it had already crossed, and subtract that from one. Multiply the remainder by the years of the nakshatra's ruling planet. A Moon 25% of the way through Rohini, ruled by the Moon with 10 years, leaves 7.5 years of Moon dasha. The calculator above does this with a lunar position accurate to a few arcseconds, so the result depends almost entirely on how accurate your birth time is.
How do I calculate antardasha periods?
Multiply the mahadasha planet's years by the antardasha planet's years and divide by 120. Venus within Venus is 20 times 20 divided by 120, which is 3 years and 4 months. Saturn within Saturn is 19 times 19 divided by 120, or 3 years and 3 days. The nine antardashas start with the mahadasha's own planet and follow the standard order, and they always add up exactly to the length of the mahadasha that contains them.
Why do different dasha calculators give different dates?
Usually because of a different year length, a different ayanamsa or a different birth time. This calculator uses 365.25-day years; a 360-day year ends a Saturn mahadasha about 100 days sooner. The Raman ayanamsa sits roughly 1 degree 27 minutes from Lahiri, which can move a Venus dasha boundary by more than two years. And every minute of birth-time difference moves the dates by 1.5 to 5 days depending on your nakshatra.
Can I calculate my dasha without a birth time?
Not reliably. Every dasha date depends on the Moon's exact position, and the Moon moves about 13 degrees a day, so an unknown birth time leaves the balance at birth uncertain by up to the full length of a planet's period. That is why this calculator asks for the time and will not run without it. If you know only the date, the nakshatra calculator will show which nakshatras the Moon passed through that day, which at least tells you which planet's dasha you were born into.
What is a pratyantardasha?
Pratyantardasha is the third level of the Vimshottari timeline: each antardasha divides into nine sub-periods by the same proportional rule. Its length is the mahadasha years times the antardasha years times the pratyantardasha years, divided by 120 squared. They range from about five and a half days for Sun within Sun within Sun up to about 203 days for Venus within Venus within Venus, so the calculator shows them only for the antardasha running now.