Vimshottari is the dasha everybody knows. It is also, in the classical scheme, one of a family. The texts describe many nakshatra-based dasha systems, and they do not apply them all to every chart. Each one has an applicability condition, and the condition is the point: a dasha applied to a chart that does not qualify for it is a timeline with no authority behind it.
Most software ignores this. It computes every system it supports and prints all of them, which looks generous and is not, because you then have several conflicting timelines and no basis for choosing between them.
The free kundali tool here computes nine nakshatra dasha systems and, for each one, reports whether the condition is met, not met, or cannot be determined from what it holds. Three systems return “cannot determine” on every chart, by design, and the page below explains why that is the better answer.
The nine systems
| System | Total | Lords in cycle | Applicability condition |
|---|---|---|---|
| Vimshottari | 120 years | 9 | Universal. The default of the tradition, and the system every other one is compared against |
| Ashtottari | 108 years | 8 | Rahu in a kendra or trikona from the lord of the Lagna. Computed |
| Shodashottari | 116 years | 8 | Bright fortnight by day, or dark fortnight by night, with the Moon in a movable-group nakshatra. Authorities differ. Not determined |
| Dwadashottari | 112 years | 8 | The Lagna falling in a Venusian navamsa. Not determined |
| Panchottari | 105 years | 7 | A Cancer Lagna, in the Dwadashamsa of Cancer. Computed in part |
| Shatabdika | 100 years | 7 | Birth in the nakshatra of Vasishtha, or per some authorities a Sun-ruled navamsa rising. Not determined |
| Chaturashiti-sama | 84 years | 7 | The lord of the 10th house occupying the 10th house itself. Computed |
| Dwisaptati-sama | 72 years | 8 | The Lagna lord in the 7th, or the 7th lord in the Lagna. Computed |
| Shashtihayani | 60 years | 8 | The Sun occupying the Lagna. Computed |
Six conditions are evaluated against your chart and answered yes or no. Three are not, and are labelled as such.
How each timeline is built
All nine share one algorithm, which is worth stating because it is where free tools most often go wrong.
- The birth nakshatra selects the starting lord, using that system’s own nakshatra-to-lord mapping. These mappings differ. Vimshottari cycles nine lords starting from Ketu at Ashwini. Ashtottari counts from Ardra in groups of three and four. Every system has its own table.
- The portion of the nakshatra already elapsed at birth is the portion of that first lord’s period already spent. So the first period in your timeline is the balance, not the full length. A tool that starts you at the beginning of the first mahadasha is wrong by up to the whole length of that period.
- Thereafter the sequence cycles in that system’s fixed order, with that system’s own year allotments.
The tool shows the balance explicitly. Each system’s summary line reads as the total cycle length followed by the balance at birth, for example a 120-year cycle with 4.3 years of Venus remaining.
Everything on this panel is computed in your browser from the Moon’s sidereal longitude. No network call is made, and the source is unminified JavaScript you can read.
Why “cannot determine” is the right answer
Three systems, Shodashottari, Dwadashottari and Shatabdika, return an honest undetermined on every chart. The reasons are specific.
Dwadashottari requires the Lagna to fall in a Venusian navamsa. The tool does not compute the navamsa lagna, so it cannot evaluate that condition. The panel says so in those words, and then presents the timeline without asserting that it applies.
Shodashottari depends on a combination of fortnight, time of day and a nakshatra group whose membership differs between authorities. Where sources disagree on the rule itself, computing a confident verdict would be manufacturing certainty that does not exist.
Shatabdika turns on a birth-nakshatra condition that some authorities restate as a navamsa condition instead. The same problem.
There are three ways a tool can handle this. It can hide the system, which loses information. It can print the timeline and let you assume it applies, which is the common choice and the misleading one. Or it can compute the timeline, show it, and label the applicability honestly.
The third is more useful because it separates two different questions. What does this dasha’s timeline look like? is always answerable from the Moon’s longitude. Does the tradition apply this dasha to this chart? sometimes is not. Collapsing the two, so that a printed timeline implies an endorsement, is where the misleading happens.
An undetermined label also tells you something actionable: if you know your navamsa lagna, you can settle the Dwadashottari question yourself in a few seconds. A tool that printed it silently would have taken that decision away from you without saying so.
Vimshottari, to four levels
Vimshottari gets its own panel, separate from the conditional systems, and it drills to four levels: Mahadasha, Antardasha, Pratyantardasha and Sookshmadasha. The tree is interactive, and the currently running period is highlighted at each level.
Its 120-year cycle runs Ketu 7, Venus 20, Sun 6, Moon 10, Mars 7, Rahu 18, Jupiter 16, Saturn 19, Mercury 17. The starting lord comes from the birth nakshatra, and the balance at birth is proportional to the part of that nakshatra the Moon had already crossed.
Two further systems sit alongside it in their own panels: Yogini dasha, the 36-year eight-fold cycle, and Chara dasha, the Jaimini rashi dasha. Those are not nakshatra dashas, so they are not part of the nine on this page.
Reading the panel
| Badge | Meaning |
|---|---|
| Universal | Vimshottari. Applies to every chart |
| Condition met | The classical condition was evaluated against your chart and is satisfied |
| Condition not met | Evaluated and not satisfied. The timeline is shown, without endorsement |
| Cannot determine | The tool does not hold the input the condition needs, and says so rather than guessing |
Expanding a system shows the full condition in prose, then the complete period table: lord, length, start date, end date, for the whole cycle. Periods shorter than a year are shown in months.
The summary strip at the top counts the systems computed, the conditions met by your chart, and your birth nakshatra, which is the input every one of the nine depends on.
What a dasha is, and is not
The panel closes with the same framing every rule engine on this site uses: a dasha is a period whose character the chart describes, not a schedule of events. In this reading it maps karma coming to fruition, and what is done inside that period remains purushartha, your own effort, one of the factors behind every outcome, not a spectator to the rest.
That framing is why the tool is comfortable showing you a Saturn mahadasha without dressing it up or apologising for it.
Known limits
- Three of the nine conditions are undetermined, for the reasons given above.
- The Panchottari condition is evaluated on the Lagna sign alone. The full classical condition adds a Dwadashamsa requirement that the tool does not test, so a “condition met” here should be read as the Lagna half of the condition being satisfied.
- Antardasha subdivision is provided for Vimshottari, not for the eight conditional systems, which are shown at mahadasha level.
- Kalachakra dasha, which is nakshatra-pada based rather than nakshatra based, is not implemented.
- Period lengths use a year of 365.2425 days. Different software uses slightly different year lengths, so dates can differ by a few days across tools even when the method is identical.
Run it on your chart
Open the free kundali tool, enter your birth details, and all nine systems compute at once alongside the four-level Vimshottari tree. Everything exports as a free PDF from the same screen.
Related: the 31 dosha conditions, the 26 yoga rules, Ashtakavarga for judging the transits that run inside a dasha, and what the whole tool computes.
Frequently asked questions
↳ Is there a free Vimshottari dasha calculator with sub-periods?
Yes, on the kundali tool here. Vimshottari drills to four levels, Mahadasha, Antardasha, Pratyantardasha and Sookshmadasha, as an interactive tree with the currently running period highlighted at each level. No account is needed and the whole report exports as a PDF.
↳ What is my dasha balance at birth?
It is the unspent part of the first mahadasha, and it depends on how far the Moon had travelled through your birth nakshatra at the moment of birth. If the Moon was a quarter of the way through, three quarters of that lord's period remained. The tool computes this for all nine systems and shows the balance on each system's summary line, so you can see at a glance where your timeline starts.
↳ Which dasha system should I use?
Vimshottari, unless you have a specific reason not to. It is the universal system in the tradition and the one every other is compared against. The eight conditional systems are meant to be used when their classical condition is satisfied, which is exactly what the tool tells you. If Ashtottari reports its condition met for your chart, that is the tradition's own signal that it is worth reading alongside Vimshottari.
↳ Why does the tool say a dasha cannot be determined?
Because the condition needs an input the tool does not compute. Dwadashottari, for example, requires the Lagna to fall in a Venusian navamsa, and the navamsa lagna is not calculated in this engine. Rather than print the timeline as though it applied, or hide the system entirely, the tool shows the timeline and labels the applicability as undetermined. The timeline itself is always computable from the Moon's longitude; the endorsement is not.
↳ What is Ashtottari dasha and does it apply to me?
Ashtottari is a 108-year cycle of eight lords, with its own nakshatra mapping counted from Ardra in groups of three and four. The classical condition most commonly cited is Rahu occupying a kendra or trikona from the lord of the Lagna. The tool evaluates that condition against your chart and reports met or not met, so you get an answer rather than a timeline you have to qualify yourself.
↳ Do these calculations happen on a server?
No. All nine nakshatra dasha systems are computed in your browser from the Moon's sidereal longitude, with no network call. The code is unminified JavaScript served from this site, so the tables, the sequences and the applicability tests can all be read directly rather than taken on trust.