Relationship Astrology

Synastry

Compare two birth charts: seven dimension scores across five relationship types, with your strongest side and where it takes the most work

Person 1

Person 2

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About This Tool

Synastry is the relationship technique of overlaying two birth charts and studying the aspects between them. Maxis scores the aspect matrix across seven relationship dimensions with a transparent model, presented on an everyday grading scale.

What it does

Compare two charts to reveal relationship dynamics.

Who it’s for

For those exploring the compatibility and dynamics between two people.

What you need

Two people’s birth data

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Frequently Asked Questions

What is synastry?

A comparison of two birth charts: the aspects one person’s planets make to the other’s planets and points describe the dynamics between them.

How is the synastry score calculated?

Seven relationship dimensions are scored from the aspect matrix and calibrated against a reference sample of real couples. Each aspect type and planet pair uses its own orb tolerance.

Does a low score mean the relationship won’t work?

No. The score measures how easily energy flows between the charts; it cannot measure effort, communication or timing. Hard aspects often mark the areas where a relationship grows.

What is the difference between synastry and a composite?

Synastry is two separate charts facing each other; a composite is a single "relationship chart" derived from both. Read together, they complete the picture.

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