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Synastry Chart Calculator
Enter two sets of birth details to see how your charts interact — aspects, compatibility scores, and a midpoint composite.
What is synastry?
Synastry is the comparison of two natal charts to see how the planets in one person's sky interact with the planets in another's. Tight aspects between luminaries (Sun, Moon), inner planets (Mercury, Venus, Mars), and chart angles reveal real relational dynamics — chemistry, communication, conflict, and long-term potential.