Create Your Composite Chart

A composite chart treats a relationship as if it were its own entity, with its own birth chart. It's calculated by taking the midpoint of each planet pair across the two natal charts — your Sun and theirs become a composite Sun, your Moon and theirs become a composite Moon, and so on.

Synastry compares two charts side-by-side — it describes how two people meet (whose Mars touches whose Venus). A composite chart merges them into one — it describes the relationship as a third party, with its own character independent of either person. Use synastry to read the dynamic between you; use the composite to read the relationship itself.

Calculations use Swiss Ephemeris. Midpoints are computed to the minute of arc; the geographic midpoint uses spherical geometry so it stays accurate even across the international dateline.

We use the geographic midpoint between both birth places for house calculations, treating it as the relationship's 'birthplace'. The composite MC is derived from the midpoint of both natal MCs.

Yes. Generate unlimited composite charts without signing up. Sign up only if you want to save profiles and access them anytime.

Use synastry when you want to know what you're each doing to the other — the attractions, the friction, the unconscious projections. Use the composite when you want to know what the relationship *is* — what kind of entity you've created, what its concerns are, where it's going. Most practitioners read both.