Two charts
We compute both natal charts independently with full house systems, then overlay them on a single dual-wheel.
Today · Thursday, June 4, 2026NASA JPL DE440S · Placidus · 100k cities
Relationships · Synastry
Free synastry chart
Two natal charts, overlaid wheel-on-wheel, with every inter-chart aspect drawn at the arc-minute.
Two birth records
Synastry is the side-by-side reading of two charts as a single field. Each chart stays its own — your Sun, your Saturn, your Moon — and on top of that we draw every aspect from one chart to the other. A natal Mars conjunct partner’s Venus, partner’s Moon trine your Sun: these are the contacts therapists, astrologers and frankly anyone who’s been in a long relationship circle back to.
Our calculator gives you the full bi-wheel and the complete aspect table (conjunctions, oppositions, squares, trines, sextiles) with orbs. Save the comparison to your dashboard for AI relationship interpretation and composite chart generation.
NASA JPL DE440SSkyfieldInter-chart aspectsTropical zodiac
What this calculator does
Inter-aspects
Every planet in chart A is checked against every planet in chart B for major aspects within standard orbs.
A relationship map
You get the wheel plus a clean list of which planets are talking to which — the actual mechanics of the chemistry.