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Two Charts Together
Before you begin
Comparing two charts is as old as the charts. Ptolemy reads a marriage by where each person's Sun and Moon fall against the other's (Tetrabiblos IV.5); modern synastry lists every aspect between the two charts — planet to planet, and to the angles when the birth times are known — and notes where each person's planets fall in the other's houses.
Two newer charts sit beside it. The composite (Robert Hand, 1975) puts each planet at the midpoint of the pair's two positions: one chart for the two. The Davison chart (Ronald Davison, 1970s) is a real chart, cast for the moment and place exactly halfway between the two births. And draconic synastry turns each chart so its own North Node is 0° Aries before the angles are taken.
None of it describes the two people, and there is no score here. Two charts make angles; what the tradition has written about each angle is beside it, and that is where this page stops.
For one chart on its own, with the readings: Your Birth Chart
What this page sends, and what it keeps
Two sets of birth details are sent to satincradle.com, which passes each to the calculation service — freeastroapi.com — and returns the planets' positions: two requests, and one more if you ask for the Davison chart. The angles, the composite and the draconic charts are worked out in your browser from those positions; nothing else is sent.
We do not log or store what you enter, and nothing is saved in your browser. Come back tomorrow and you will be asked again.