Synastry Chart Calculator
Astrology Compatibility Analysis
Compare two birth charts to see how your planets interact. Get detailed aspect analysis, compatibility insights, and AI-powered relationship guidance.
Complete Synastry Chart Analysis
Everything you need to understand the astrological dynamics between two people
Cross-Chart Aspect Analysis
Calculate the exact angular relationships between planets in both birth charts. See conjunctions, trines, squares, sextiles, and oppositions with precise orb data.
Interactive Aspect Reports
Explore detailed descriptions for each planetary aspect between the two charts, with strength ratings and compatibility interpretations.
AI Relationship Insights
Get personalized AI analysis of your relationship dynamics, including communication patterns, emotional needs, attraction, and growth areas.
Relationship Chat AI
Chat with our AI about your relationship using both birth charts as context. Ask specific questions about compatibility, challenges, and potential.
How Synastry Analysis Works
A step-by-step guided experience from chart comparison to full relationship insights
Charts and Compatibility Overview
See both birth charts rendered side by side, along with your combined synastry wheel showing how the two charts overlay.
Planetary Positions Comparison
Explore each planet's sign and house placement for both people. Understand where your charts align and where they differ.
AI Relationship Analysis
Receive a comprehensive AI-generated reading about your relationship dynamics, covering compatibility strengths and areas for growth.
Aspect Analysis
Dive into every cross-chart aspect between your planets. See the exact angles, orbs, strength levels, and what each connection means.
Complete Synastry Report
Get a downloadable PDF with a full compatibility analysis covering all aspects, planetary positions, and relationship insights.
What You Will Learn from Synastry
Practical relationship insights based on real astrological data
Understand Attraction Patterns
See the Venus and Mars connections that drive physical and emotional attraction between two people.
Improve Communication
Identify Mercury and Moon aspects that show how you communicate and process emotions together.
Spot Growth Opportunities
Challenging aspects (squares, oppositions) often point to areas where you push each other to evolve.
Confirm Compatibility Strengths
Harmonious aspects (trines, sextiles) reveal where your energies flow easily and naturally together.
Explore Any Relationship Type
Synastry works for romantic partners, friends, family members, business partners, and any meaningful relationship.
Get Actionable Advice
AI-powered insights translate complex astrological data into practical relationship guidance.
±0.01°
PrecisionPlanetary aspects calculated to high decimal accuracy500+
CombinationsOver 500 planetary aspect interpretations available17
LanguagesSynastry analysis and AI insights in multiple languagesSwiss
EphemerisAstronomical accuracy from the Swiss Ephemeris dataExplore Related Chart Types
Combine synastry with other analysis tools for deeper understanding
Synastry Chart FAQ
Common questions about relationship compatibility analysis and synastry charts
A synastry chart compares two birth charts by calculating the angular relationships (aspects) between planets in one chart and planets in the other. For example, if your Venus forms a trine to your partner's Mars, that aspect describes a specific type of attraction and energy flow. Synastry reveals compatibility, challenges, and dynamics between any two people.
Exact birth times provide the most complete analysis, including house overlays that show where each person's planets fall in the other's chart. Without birth times, the aspect analysis between planets is still accurate, but house placement information will be missing. If one person has an approximate time, the results are still very useful.
Synastry reveals the dynamics, strengths, and challenges between two people, but it does not predict whether a relationship will succeed or fail. Even charts with many challenging aspects can describe passionate, growth-oriented relationships. Harmonious charts may indicate ease but not necessarily depth. Use synastry to understand the relationship's nature, not to judge its outcome.
Synastry compares two separate birth charts and analyzes how each person's planets interact with the other's. A composite chart creates a single new chart by finding the midpoints of both charts, representing the relationship itself as a third entity. Synastry shows interpersonal dynamics. Composite shows the relationship's core identity and purpose.
Yes. Synastry works for any type of relationship, not just romantic ones. You can analyze the dynamics between friends, parents and children, siblings, business partners, or colleagues. The planetary aspects describe patterns of interaction, communication, and energy exchange that apply to any meaningful connection.
The Relationship Chat AI is an interactive feature where you can ask specific questions about your relationship. It uses both birth charts as context to provide personalized answers about compatibility, communication, timing, and growth areas. You can ask follow-up questions and have a natural conversation about your relationship dynamics.
Ready to Analyze Your Compatibility?
Enter birth details for two people and get a complete synastry chart with AI relationship insights.