Free tool
Porutham Calculator
All ten poruthams from two birth charts, in the Kerala and Tamil traditions at once — including the koot they disagree about.
Person 1 — by convention the groom's details.
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What porutham matching is, and how it differs from gun milan
Porutham is the South Indian approach to marriage matching. It reads the two birth nakshatras against ten checks — Dina, Gana, Mahendra, Stree-deergha, Yoni, Rasi, Rasi-adhipathi, Vasya, Rajju and Vedha — and reports which pass. In Kerala it is usually called porutham; in Tamil practice the same ten are the thirumana porutham.
It is not the same as Ashtakoot gun milan, the North Indian system that scores a pair out of 36. The koots overlap in name but not in method or weighting, and the two produce different answers on the same pair. Neither is a more accurate version of the other; they are separate traditions, and a family will use the one their community uses.
This calculator does not ask you to choose. It runs the Kerala and the Tamil reading on the same two charts and shows both, because the interesting cases are the ones where they differ.
How to read your result
Two totals sit at the top, one per tradition, each out of ten. Read them as two opinions rather than an average — there is no meaningful way to combine them, and the tradition your family follows is the one that applies.
Below them, every porutham appears once with both traditions' verdicts side by side. Where they agree, that is the settled reading. Where they disagree, the row is highlighted and a note names the koot.
A porutham that objects is not a veto. In practice a match is weighed as a whole, several of the ten carry recognised exceptions, and the household's own custom decides how much any single objection counts. A calculator can tell you what the checks say; it cannot tell you what they are worth to you.
Where the two traditions part company
On most pairs the Kerala and Tamil readings return the same ten verdicts and the same total. Running 81 pairs through the engine, they agreed on 74 of them.
The other seven disagreed — and every one of those disagreements was the same koot: Rajju. The traditions map a birth star to a different limb of the rajju scheme, so the same girl can read as Nabhi rajju in one and Kanta in the other. When that shifts both partners onto the same limb, one tradition raises the same-rajju objection and the other does not.
That matters because Rajju is not a minor check in South Indian practice — it is among the objections families take most seriously. A calculator that silently picked one tradition would show a clean match to someone whose own community's reading raises a serious objection, and they would have no way to know. That single fact is why this page computes both.
Method and provenance
Both readings come from the same Swiss Ephemeris chart computation used everywhere else on this site — sidereal, Lahiri ayanamsa — so the birth stars underneath the two traditions are identical. The only difference is the scheme applied on top.
The two are separate endpoints, requested together and merged for display. Either can fail on its own: if one tradition does not answer, the page shows the one that did rather than failing entirely, and says which is missing.
The disagreement rate quoted above is measured, not asserted — 81 pairs, 7 splits, all on Rajju — and the check is pinned in the test suite, so if a future engine change unified the schemes this page would stop claiming a distinction it no longer computes.
What this does not tell you
It does not tell you whether to marry someone, and no arrangement of ten checks does. It reports what the classical rules say about two birth stars.
It does not include the Ashtakoot 36-guna score, the Mangal dosha cross-check or the dasha comparison — those are on the kundli matching tool, and a family using the North Indian system should start there instead.
It reads only the nakshatras. Porutham traditionally sits inside a wider judgement that includes the seventh house, its lord, and the Navamsa — none of which this page touches.
And it depends on both birth times. The nakshatra is the Moon's, and the Moon changes nakshatra roughly every day, so a wrong date matters more here than a wrong hour — but an uncertain time can still move a borderline chart.
Frequently asked
- What is thirumana porutham?
- The Tamil name for the ten-check nakshatra matching used in South Indian marriage matching. Kerala practice calls the same ten poruthams. This calculator runs both readings on the same pair of charts and shows them together.
- How is porutham different from gun milan?
- Gun milan is the North Indian Ashtakoot system, scored out of 36 across eight koots. Porutham is the South Indian system, ten checks read pass or fail. They share some koot names but not their method or weighting, and they will disagree on the same pair. Neither corrects the other — a family uses the system their community uses.
- Why do the Kerala and Tamil results sometimes differ?
- Almost always because of Rajju. The two traditions assign a birth star to a different limb in the rajju scheme, so one may see both partners on the same limb — the same-rajju objection — where the other does not. Across 81 test pairs the two agreed on 74 and split on 7, every split on Rajju.
- Which tradition should I follow?
- The one your family follows. That is not a hedge — porutham is a community practice, and there is no neutral vantage point from which one scheme is more correct. The page shows both so you can see what each says, including when they disagree about your own chart.
- How many poruthams need to match?
- There is no universal threshold, and any site quoting one is quoting a custom rather than a rule. Practice varies by community, and several of the ten carry recognised exceptions. What the tool gives you is which checks pass and which object, with the reasoning for each — the weighing is done by people who know the families.
- Do I need exact birth times?
- Less than for a lagna-based reading, but they still help. Porutham is read from the Moon's nakshatra, and the Moon changes nakshatra roughly once a day — so the date matters most, and an uncertain time only moves a chart that was already near a boundary.