Vimshottari dasha step by step

Published 9 Oct 2026

By the end of this article you will be able to compute a Vimshottari dasha from the Moon's longitude with a calculator: the balance at birth, the mahadasha dates, and the antardasha and pratyantar splits. Two fictional charts are worked through, with the arithmetic checked against software output.

Definitions

• Nakshatra: one of 27 equal divisions of the sidereal zodiac, each 13°20′, or 800 arc-minutes.
• Nakshatra lord: the planet ruling a nakshatra. The nine lords repeat three times from Ashwini.
• MD (mahadasha): the main period of a planet. AD (antardasha): a sub-period inside an MD. PD (pratyantardasha, pratyantar): a sub-period inside an AD.
• Balance at birth: how much of the first MD remains when the person is born.
• Ayanamsa: the offset between tropical and sidereal longitude. Lahiri is the common Parashari choice.

The method, step by step

Step 1: The order and the years

Vimshottari ("one hundred and twenty") gives each of nine planets a fixed number of years. They run in this order, and the same order assigns lords to the nakshatras starting from Ashwini:

The years add up to 120. After Mercury the cycle returns to Ketu.

Step 2: Find the Moon's nakshatra and how far it has gone

Convert the Moon's sidereal position to arc-minutes from the start of its nakshatra. A quick way: write the longitude from 0° Aries, divide by 13°20′, and the whole part tells you how many nakshatras have passed; the remainder is the distance travelled in the current one.

Step 3: Compute the balance

Balance = (800′ − arc-minutes travelled) ÷ 800′ × lord's years.

Equivalently, each arc-minute the Moon has still to travel in the nakshatra is worth (lord's years ÷ 800) years of MD.

Step 4: Date the mahadashas

The first MD ends at birth + balance. Each later MD starts where the previous one ended and lasts its full years. Working backwards, the first MD began at birth − (lord's years − balance). Software usually lists nine MDs starting from that earlier date, which covers 120 years.

To turn years into dates you need a year length. A year of 365.25 days is a common choice and is the default here. It is a parameter, not a fixed rule, because not every astrologer uses it (see below).

Step 5: Split each MD into ADs

AD length = MD years × AD lord's years ÷ 120.

The first AD belongs to the MD lord, and the rest follow the Vimshottari order from there. In a Rahu MD the ADs run Rahu, Jupiter, Saturn, Mercury, Ketu, Venus, Sun, Moon, Mars.

Step 6: Split each AD into PDs

PD length = AD length × PD lord's years ÷ 120, starting with the AD lord. The same rule continues to deeper levels if you want them.

This is exactly what AstroReads computes: Moon longitude to elapsed fraction of the nakshatra, balance of the first MD, nine MDs over 120 years, and proportional splits down to the third level (PD).

Worked example

Both charts are fictional births, used only to illustrate the method. The Moon positions are sidereal (Lahiri), and the dasha uses 365.25-day years.

Example A: Moon in Chitra

• Birth: 14 Mar 1990, 06:20 IST, Pune (00:50 UTC).
• Moon: Virgo 28°28′, Chitra pada 2. Chitra is ruled by Mars (7 years).

Chitra runs from Virgo 23°20′ to Libra 6°40′.

The software reports a balance of 4.30 years. The small difference comes from rounding: the printed position is rounded to the nearest arc-minute, and in Chitra one arc-minute is worth 7 ÷ 800 = 0.00875 years, about three days. The software works from the unrounded longitude.

From there the MD dates follow:

Mars MD began about 2.70 years (7 − 4.30) before birth, and ended 4.30 years after it, on 1994-07-02.

The ADs of the Rahu MD (18 years). Each AD is 18 × lord's years ÷ 120:

The nine ADs add up to 18.00 years.

Running on 2026-10-09. Jupiter MD (2012-07-01 to 2028-07-01), Rahu AD (2026-02-06 to 2028-07-01), Jupiter PD (2026-06-17 to 2026-10-12). You can check each level:

• Rahu is the last AD of a Jupiter MD, so it ends with the MD. Its length is 16 × 18 ÷ 120 = 2.40 years, which takes it back from 2028-07-01 to 2026-02-06.
• Inside that AD, the Rahu PD is 2.40 × 18 ÷ 120 = 0.36 years (about 131 days), from 2026-02-06 to 2026-06-17.
• The Jupiter PD is 2.40 × 16 ÷ 120 = 0.32 years (about 117 days), from 2026-06-17 to 2026-10-12.

Example B: Moon in Shravana

• Birth: 02 Aug 1993, 21:45 IST, Lucknow (16:15 UTC).
• Moon: Capricorn 18°33′, Shravana pada 3. Shravana is ruled by the Moon (10 years).

Shravana runs from Capricorn 10°00′ to 23°20′.

By hand this rounds to 3.59 years, but the software reports 3.58 years. Trust the software's figure here. In Shravana one arc-minute is worth 10 ÷ 800 = 0.0125 years, about 4.6 days. The unrounded Moon is a fraction of an arc-minute further into Shravana than the printed 18°33′, which leaves slightly less of the MD to run. Moon MD therefore runs from 1987-03-04 to 1997-03-03, about 6.42 years before birth and 3.58 years after.

The first AD of the Mars MD is Mars itself: 7 × 7 ÷ 120 ≈ 0.41 years, from 1997-03-03 to 1997-07-30. Rahu AD follows (7 × 18 ÷ 120 = 1.05 years), to 1998-08-18.

On 2026-10-09 Example B runs Jupiter MD (2022-03-03 to 2038-03-03), Saturn AD (2024-04-21 to 2026-11-02) and Jupiter PD (2026-07-02 to 2026-11-02). In a Saturn AD the PDs start from Saturn, so Jupiter is the last PD and ends with the AD.

Where traditions differ

Year length. The dasha arithmetic is agreed; converting years to dates is not. Common choices are:

The 360-day year changes dates by many months late in life; the 365.2422-day year barely moves them. AstroReads uses 365.25 days; the year length is fixed in the product for now. Each of these choices has serious practitioners behind it.

Ayanamsa. The balance depends on the Moon's sidereal longitude, so the ayanamsa moves it directly. Lahiri and the KP (Krishnamurti) ayanamsa differ by only a few arc-minutes; at lord's years ÷ 800 per arc-minute, that shifts dates by days to weeks. Raman's ayanamsa differs from Lahiri by more than a degree, which shifts dates by months and can move the Moon into a different nakshatra. The product uses Lahiri for Parashari work and the Krishnamurti ayanamsa for KP; neither can be changed yet.

Starting point. Starting Vimshottari from the Moon's nakshatra is the standard practice described in Brihat Parashara Hora Shastra and followed almost universally. Some texts and teachers describe alternatives: starting from the lagna's nakshatra, and the Utpanna variation, which starts from a nakshatra counted from the birth star (commonly the fifth). These are minority methods. We start from the Moon only.

Depth. Vimshottari can be split below pratyantar into sookshma (fourth level) and prana (fifth level) by the same proportional rule. At those levels a period can last only days or hours, so the result depends heavily on an exact birth time. We compute to pratyantar only; if you work at sookshma or prana, use the same formula on the PD.

Day count and time of day. Because 365.25-day years carry quarter-days, period boundaries can fall a day apart from one MD to the next (2012-07-01 for one, 2047-07-02 for another). Some software rounds to calendar days or uses local time; others keep the exact moment in UTC. A one-day difference between programs is usually this, not an error.

Common mistakes

• Using tropical longitude. The Moon must be sidereal; a tropical Moon is off by more than 20° and usually in a different nakshatra.
• Counting the elapsed part as the balance. The balance is the part still to run, not the part travelled.
• Starting ADs with the wrong lord. The first AD of any MD belongs to that MD's lord.
• Splitting by 9 instead of by years. ADs are proportional to the lords' years, not equal ninths.
• Trusting hand-rounded arc-minutes for close calls. One arc-minute is worth 3 to 9 days of MD depending on the lord; check against unrounded software output before calling a date.

Sources

• Brihat Parashara Hora Shastra: the Vimshottari order, years and sub-period rule.
• Phaladeepika (Mantreswara): results of dashas and antardashas.
• K.S. Krishnamurti, KP Readers: the use of Vimshottari periods with star and sub lords in KP timing.
• K.N. Rao, Timing Events Through Vimshottari Dasha.