Accuracy first — every position comes from DE440, NASA JPL's most precise planetary ephemeris.
Accuracy first — every position comes from DE440, NASA JPL's most precise planetary ephemeris.
Nadi carries eight of the thirty-six points in Ashtakoot matching — more than Varna, Vashya, Tara and Yoni together. It is also the koota with the longest list of classical exceptions. The chart below shows which nakshatra falls in which nadi; the calculator checks a real pair against those exceptions.
Enter both birth details and see whether this dosha applies to that pair, and if it is cancelled, which classical rule cancels it.
Enter both sets of birth details to see whether the dosha applies.
Each of the twenty-seven nakshatras belongs to one of three nadis — Aadi, Madhya or Antya. The classical texts read these as constitutional groupings rather than as a quality one nakshatra has and another lacks: no nadi is better than another, and there is nothing in a chart that is improved by falling in one rather than a second.
Nine nakshatras in each, in the order they run from Ashwini. Find both birth nakshatras below: if the two sit in the same column the dosha is present, and if they sit in different ones it is not.
Nadi Dosha is present when both charts fall in the same nadi. It is the only koota scored all-or-nothing: eight points when the nadis differ, zero when they match, with nothing in between. That single step is why two couples separated by one nakshatra can sit eight points apart on a thirty-six point scale, and why a total read without the koota table beside it says very little.
A dosha that is cancelled is not the same as a dosha that was never there, and neither is the same as one that stands. The classical literature carries a substantial body of exceptions under which Nadi Dosha does not apply despite both charts sharing a nadi — the same rasi with different nakshatras, a common rasi lord, an established friendship between the lords, and others.
Whether a specific exception applies to a specific pair is not something a chart can answer — several of these rules depend on rasi lords and the relationship between them, which means two couples sharing a nadi can have entirely different outcomes. The rules here tell you what is possible; only running both charts tells you what happened. The threshold of eighteen out of thirty-six is a convention, not a verdict, and practitioners weigh Nadi far more heavily than its share of the points suggests.