Free Synastry Calculator
Compare two birth charts and see the synastry aspects astrologers actually read for compatibility — Sun-Moon, Venus-Mars, ascendant and Saturn contacts. Free and instant.
FAQ
What is synastry?
Synastry is the astrological comparison of two birth charts. It overlays one person's planets on another's and measures the aspects between them — the angles that show where two people attract, ease, or grate. It's the technique astrologers use to read relationship compatibility.
Which synastry aspects matter most?
The classic relationship contacts are Sun-Moon (identity meets emotional need), Venus-Mars (the attraction signature), ascendant contacts (instant chemistry), and Saturn contacts (durability). This calculator highlights close aspects between exactly those points.
Is the synastry calculator accurate?
The aspect math is exact — it computes real planetary positions and the angles between two charts. Interpreting what those aspects mean for a relationship is the art, not a science. Use the result as an informed starting point, not a prediction.
Can synastry tell me if someone is my soulmate?
It can show you where two charts resonate and where they strain, which is genuinely useful. But no chart names a soulmate. Strong synastry describes potential; what you build with it is up to two real people. Treat it as a lens for understanding, not a guarantee.