Free Western Astrology Compatibility Calculator
Discover your relationship dynamics. Calculate and compare your Sun, Moon, and Rising signs (The Big Three) with your partner.
Western Astrology Compatibility
Analyze your Big Three to see how your core personalities and emotions interact.
What is Synastry?
Synastry is the art of relationship astrology. Instead of reading one birth chart, it involves laying two natal charts on top of each other to see how the planets interact.
By analyzing the mathematical angles (aspects) between your planets and your partner's planets, you can uncover the areas of natural harmony, intense attraction, and potential friction in your relationship.
The Most Important Compatibility Factors
While Sun sign compatibility is popular, professional astrologers know that the Moon and Ascendant are far more important for long-term relationships. Your Moon compatibility dictates emotional harmony, while your Ascendant compatibility determines your day-to-day rhythm and how you appear to the world as a couple.
Decoding Your Big Three Compatibility
1. The Sun: Core Identity
Your Sun signs reveal your core life purpose. Do your fundamental goals align? For example, a home-loving Cancer Sun might struggle with a freedom-seeking Sagittarius Sun.
2. The Moon: Emotional Needs
This is the most critical factor for domestic bliss. If your Moon signs are in compatible elements (e.g., Earth and Water), you will intuitively understand how to nurture and support each other.
3. The Rising Sign: Social Persona
Your Rising signs show how you present yourselves to the world. A compatible Rising sign combination means you operate well as a team in social situations and daily life.
Unlock the Deeper Layers
This free tool only scratches the surface. To see the full picture—including how your Venus (love language) and Mars (sexual chemistry) interact, and which of your 12 Houses your partner's planets activate—download the YuanYu App. Get a professional-grade Synastry report instantly.