Two charts, overlaid.

Every body in one chart measured against every body in the other — 144 pairs, not the 66 of a single chart. The angles are exact; what they mean is yours to read.

Both birth details

Times are not strictly required for planet-to-planet contacts, but they sharpen the Moon.

What synastry measures

One chart is laid over the other and every angle between one person's bodies and the other's is measured. Where an angle lands close to one of these figures, the pair is said to be in aspect. Nothing here is a score — an aspect either forms inside its orb or it does not.

Aspect	Angle	Traditionally read as
conjunction	0°	The two bodies act as one. Neither easy nor hard by itself.
sextile	60°	Opportunity that has to be taken up rather than arriving.
square	90°	Friction. The classical reading is tension that forces movement.
trine	120°	Ease, to the point of being taken for granted.
opposition	180°	Pull in two directions — often attraction and strain together.

Synastry or kundli matching?

Synastry — this page

Western, tropical, and aspect-based. Uses every body in both charts, so it needs two accurate birth times. Produces a list of connections, not a number.

Ashtakoota matching

Vedic, sidereal, and almost entirely about the two Moons. Produces a score out of 36. It is what an Indian family will actually ask for, and it answers a narrower question.

They disagree constantly, and that is not a fault in either. They use different zodiacs, different bodies and different rules. Agreement would be the surprising outcome.

No compatibility percentage

Two charts either have a Venus–Mars trine or they do not — that part is arithmetic. Turning it into a single percentage implies a precision the method does not have, and people make real decisions on those numbers.

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