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96Astro API

By topic / Synastry API

Synastry API: how two charts meet

Compare two birth charts: every aspect between them, a score, a composite chart, and readings on love, friendship and lasting bonds. There is a simple Sun and rising match too, for people with no birth time.

What people build with it

  • Compatibility in a dating app
  • Couple reports
  • Friendship features

The endpoints

  • Synastry Chart

    Both people's positions, the aspects between their charts, and a compatibility block with score, Sun and Moon compatibility and a verdict.

    POST /v1/western/synastry-chart

    1 credit

  • Synastry Compatibility Score

    A synastry compatibility score with Sun and Moon compatibility, aspect counts and a verdict.

    POST /v1/western/synastry-compatibility

    1 credit

  • Synastry Aspects

    Inter-chart aspects between two people, split into harmonious and challenging, with orb and meaning.

    POST /v1/western/synastry-aspects

    1 credit

  • Synastry: Everything

    Compatibility, all five domain readings ranked (career, finance, intimacy, spirituality, emotion) and the sun-sign match, in one call.

    POST /v1/western/synastry-full

    10 credits

  • Composite Relationship Chart

    A relationship chart from the midpoint of each body between two births, with houses derived from the composite midheaven at the births' midpoint latitude.

    POST /v1/western/western-composite-chart

    1 credit

  • Love Contacts

    Contacts between two charts that bear on love: Venus, Mars, the Sun and the Moon.

    POST /v1/western/western-love-contacts

    1 credit

  • Friendship Report

    Contacts between two charts that bear on friendship: Sun, Moon, Mercury and Jupiter.

    POST /v1/western/western-friendship-report

    1 credit

  • Sun and Rising Compatibility

    A compatibility percentage and verdict from two people's Sun and rising signs, scoring each pairing, with a summary. It needs no birth time.

    POST /v1/western/western-sun-rising-match

    1 credit

  • Star Sign Compatibility Report

    Both personalities and every love, friendship and lasting-bond contact between two charts, as one report.

    POST /v1/reports/report-star-sign-compatibility

    10 credits

Common questions

Does it need both birth times?
A full synastry does. western-sun-sign-match and western-sun-rising-match work from signs alone.