Relationship Chart Comparison
Compare two birth charts in a synastry biwheel and a midpoint composite wheel. The results show planetary geometry without scoring compatibility or predicting relationship outcomes.
What synastry compares
Synastry looks at angular distances across two charts. A midpoint composite places each planet halfway between its two chart positions. A complete reading also considers the individual charts, both people’s context, and the quality of the source birth data.
How to read this comparison
Cross-chart contacts
The aspect table checks every planet in one chart against every planet in the other. It includes conjunction, sextile, square, trine, and opposition within a 3° orb, sorted from closest to widest. An empty table means none of these selected contacts fits that limit.
How the composite is formed
For each matching planet, the tool calculates the midpoint of the two tropical zodiac longitudes along the shorter arc. An exact 180° separation has two possible midpoints and is marked as ambiguous. The table is a mathematical comparison, not a separate dated birth chart.
Reading individual contacts
The result lets you select a close cross aspect to read about that pair of planets and a prompt for discussion. The text describes a possible theme rather than measuring whether the people fit together. Keyboard users can select the same factors without a mouse.
What it leaves out
The calculation does not ask for locations, so it omits both people’s angles and houses as well as composite houses. It does not produce a compatibility score or relationship verdict. A useful interpretation also needs the quality of both birth records and the actual circumstances of the people involved.