Vimshottari Dasha (大运)

The Vedic Timing Engine — Which Planet Rules This Chapter of Your Life

Overview

Vimshottari Dasha (विंशोत्तरी दशा) is the master clock of Vedic astrology — the single most-consulted predictive technique in all of Jyotish. Where a birth chart shows the fixed promise of the planets, the dasha system tells you when that promise unfolds: it divides a human life into a fixed 120-year cycle of planetary periods, each ruled by one of the nine grahas, and within each period a sequence of sub-periods, and within those, sub-sub-periods, nesting three levels deep. The major period is the Maha-dasha, the chapter of life — a Jupiter Maha-dasha runs sixteen years, a Venus one twenty, a Sun one six. Inside it, the Antar-dasha (or bhukti) is the sub-chapter, and inside that the Pratyantar-dasha is the running scene. The whole edifice is anchored not on the Sun or the ascendant but on the Moon: the exact nakshatra (lunar mansion) the Moon occupied at birth fixes which planet's period you are born into and how much of it remains, and from that single seed the entire 120-year timeline unrolls deterministically. askTIAN computes the full dated timeline from its own precise sidereal astronomy — the nine Maha-dashas with their Gregorian start and end dates, each broken into its nine Antar-dashas, plus the live Maha→Antar→Pratyantar stack at any date you ask for, defaulting to today. Because the system needs only the Moon, it works even when the birthplace is unknown.

Origin & history

Vimshottari Dasha is set out by the sage Parashara in the Brihat Parashara Hora Shastra, the foundational text of Vedic astrology, as the foremost of the nakshatra-based period systems. Its name means 'of one hundred and twenty' — the total length of the cycle in years, the figure the tradition takes as the ideal full human lifespan. The cycle assigns each of the nine grahas a fixed number of years: Ketu 7, Venus 20, Sun 6, Moon 10, Mars 7, Rahu 18, Jupiter 16, Saturn 19 and Mercury 17, summing exactly to 120. The order is invariant, and which planet you begin with is determined by the Moon: the 360-degree zodiac is divided into 27 nakshatras of 13°20′ each, the nakshatras cycle through the nine lords three times over, and the lord of the nakshatra the Moon occupies at birth is the lord of your first Maha-dasha. The fraction of that nakshatra the Moon has already crossed is the fraction of the first period already elapsed — so a child born when the Moon is two-thirds through Jupiter's nakshatra is born with a third of a Jupiter Maha-dasha remaining, the famous 'balance of dasha at birth'. Each level below repeats the same logic by simple proportion: the share of a sub-period is the parent's length times the sub-lord's years divided by 120, so the nine sub-periods of any period always sum back exactly to it.

For well over a millennium Vimshottari has been the backbone of predictive Jyotish — the technique an astrologer reaches for first to time marriage, career turns, gains and losses, and the broad seasons of a life. It is read by overlaying the nature of each period's ruling planet, its dignity and house lordships in the natal chart, and the relationship between the Maha-dasha lord and the Antar-dasha lord, onto the timeline the cycle generates. Its enduring authority comes from its determinism: given an accurate birth time, the entire sequence of dates follows by arithmetic, and the same chart yields the same timeline in any competent software. The one genuine convention question is the length of a dasha-year in days — most modern tools, including AstroSage, use 365.25 days, while Jagannatha Hora and the PyJHora library use the sidereal year of 365.256364 days, a difference of under a day across a whole 120-year life; only the classical 360-day savana year diverges materially, drifting some 1.7 years over the cycle. askTIAN uses the 365.25-day year by default — the same convention its Jyotish engine already assumes, so the two agree by construction — offers the 360-day savana mode as an option, and is candid that dasha dates are soft to within a few days, dependent on birth-time accuracy and the choice of ayanamsa. The engine is verified against the published Vimshottari table for Albert Einstein (whose AA-rated birth-certificate data leaves no ambiguity), reproducing his balance of dasha and every Maha-dasha boundary to within two days, and against the independently-attested fact that Mahatma Gandhi died in his Jupiter Maha-dasha, Venus Antar-dasha.

How it works

askTIAN converts the birth date, time and timezone to a single instant and computes the Moon's true sidereal longitude with its own Meeus-precision ephemeris on the Lahiri ayanamsa — the same astronomy its Jyotish, Varga, Ashtakavarga, Panchanga and Shadbala engines share. From the Moon's longitude it finds the nakshatra and the fraction of it already traversed: the nakshatra's lord opens the dasha, and the unelapsed fraction gives the balance of that first Maha-dasha at birth. It then walks the fixed nine-lord cycle forward, assigning each Maha-dasha its years (Ketu 7, Venus 20, Sun 6, Moon 10, Mars 7, Rahu 18, Jupiter 16, Saturn 19, Mercury 17) converted to days at 365.25 days per year, to produce nine periods with exact Gregorian start and end dates spanning roughly 120 years from birth. Each Maha-dasha is subdivided into nine Antar-dashas that begin from the Maha-dasha lord itself and run in the same Vimshottari order, each lasting the Maha-dasha's length times the sub-lord's years over 120 — so the nine always sum back exactly to the parent. The first Maha-dasha and its first Antar-dasha are anchored at the birth date, showing only the balance, the universal table convention. To report the running period at any reference date (today by default), the engine locates the Maha-dasha containing that date, then the Antar-dasha within it, then computes the nine Pratyantar-dashas of that Antar-dasha and finds the one in force, returning the full Maha→Antar→Pratyantar stack with each period's dates, percent elapsed and years remaining. A transparent 0–100 score reads the benefic or malefic tone of the current stack — never a fortune. The structural invariants (the lords summing to 120, every sub-period summing to its parent, the timeline chaining without gaps) are locked by unit test, and the dated output is checked against published reference timelines.

Good for

• Building a full dated life-timeline of planetary periods from a birth chart — the nine Maha-dashas with start and end dates
• Knowing which Maha-dasha, Antar-dasha and Pratyantar-dasha is running right now, or on any chosen date
• Timing the broad seasons of a life — which planet rules a given year, and when the chapter changes
• Reading the balance of dasha at birth — which period a person is born into and how much of it remains
• Drilling into a Maha-dasha's sub-periods (bhuktis) to see the sequence of sub-chapters within it
• Adding the time dimension to a Jyotish, Shadbala or Ashtakavarga reading on the same sidereal chart
• Working without a birthplace — the dasha needs only the Moon, so date, time and timezone suffice

Use cases

Life Timeline Dashboard

Send a birth chart and the API returns the nine Maha-dashas with Gregorian dates and durations, each expandable into its nine Antar-dashas — a fully deterministic spine for a 'periods of your life' feature, no LLM required.

What's Running Now

Ask for the running stack as of today (or any date) and get the Maha→Antar→Pratyantar lords in force, with percent elapsed and years remaining — the one-line 'you are in Jupiter–Venus–Mercury until March' answer.

Balance of Dasha at Birth

Read the nakshatra lord that opens the chart and the exact balance remaining at birth — the seed every Vedic timing reading begins from, returned with the Moon's nakshatra and pada.

Layer Over the Vedic Suite

Sharing the same sidereal chart as Jyotish, Shadbala and Ashtakavarga, an app can show a planet's placement, its six-fold strength and the dates it actually rules the life — placement, power and timing on one ephemeris.

Key terms

Vimshottari Dasha

Sanskrit for 'the 120-year period system' — the foremost Vedic timing technique, dividing life into a fixed 120-year cycle of planetary periods anchored on the Moon's birth nakshatra.

Maha-dasha

The major period, the chapter of life ruled by one graha, lasting that planet's fixed number of years (Ketu 7, Venus 20, Sun 6, Moon 10, Mars 7, Rahu 18, Jupiter 16, Saturn 19, Mercury 17 — summing to 120).

Antar-dasha (Bhukti)

The sub-period within a Maha-dasha. The nine Antar-dashas begin from the Maha-dasha lord and run in Vimshottari order, each lasting the Maha-dasha length × the sub-lord's years ÷ 120, summing exactly to the parent.

Pratyantar-dasha

The sub-sub-period within an Antar-dasha — the third level of nesting, computed by the same proportional rule, giving the finely-grained running 'scene' at any moment.

Balance of Dasha

The portion of the first Maha-dasha remaining at birth, equal to the ruling planet's years times the fraction of the Moon's nakshatra not yet crossed — the seed from which the whole timeline unrolls.

Nakshatra

One of the 27 lunar mansions of 13°20′ that divide the sidereal zodiac. The lord of the nakshatra the Moon occupies at birth is the lord of the first Maha-dasha; the nakshatras cycle through the nine lords three times over.

Dasha-year

The length of a period-year in calendar days. askTIAN uses 365.25 days by default (matching AstroSage to within two days; JHora/PyJHora use the sidereal 365.256364, under a day's difference over a life); a 360-day savana mode is offered as an option.

API

The askTIAN Vimshottari Dasha API builds the full Vedic timing timeline for any birth chart on its own self-verifying sidereal astronomy: it returns the Moon's nakshatra, pada and lord, the balance of dasha at birth, the nine Maha-dashas with Gregorian start/end dates and durations, each subdivided into its nine Antar-dashas, and the live Maha→Antar→Pratyantar stack at any reference date (today by default) with percent elapsed and years remaining, plus the nine Pratyantar sub-periods of the running bhukti, a transparent 0–100 tone score and a fixed-section LLM reading. It needs only the Moon, so no birthplace is required. The method follows the Brihat Parashara Hora Shastra on the Lahiri sidereal zodiac — the same chart the Jyotish, Shadbala, Varga, Ashtakavarga and Panchanga endpoints share — with a 365.25-day dasha-year by default and an optional 360-day savana mode. It is locked by unit test against the published AstroSage table for Einstein (balance and boundaries to within two days) and Gandhi's attested Jupiter–Venus at death, with the structural invariants and a cross-check against the Jyotish engine's current Maha-dasha. Dasha timing is a symbolic clock for reflection, not prediction of fixed events; boundaries are soft to within a few days. Set interpretation:false for structured data only.

Endpoint: POST /trpc/dasha.vimshottari — 7 TIAN Points. See the API documentation and Playground.