How compatible are you, really?
Compare two birth charts and see the real connection between them.
Or check by star sign
Just want the sign-by-sign read? Pick two signs to open their full compatibility guide.
Popular compatibility pairings
Tap a pairing for the full sign-by-sign breakdown.
What astrology compatibility really measures
Astrology compatibility, known as synastry, is the study of how two birth charts interact. Instead of comparing only Sun signs, synastry lays one person's chart over the other's and measures the angles, called aspects, between every planet. Those angles describe the real texture of a relationship: where two people flow together, where they challenge each other, and what each one quietly brings out in the other.
This matters because a relationship is never just two Sun signs meeting. Your Moon wants something different from your Sun. Your Venus loves in its own language. When someone's Mars lands on your Venus, or their Moon trines your Sun, you feel it long before you can explain it. Synastry gives you the explanation, in plain terms, so a vague "we just click" becomes "your Venus sits right on my Mars, which is why the attraction is instant."
How the Astrologyic compatibility calculator works
The calculator above casts a full tropical birth chart for each person from their birth date, and from their birth time and city when you add them. It then compares every planet in chart one to every planet in chart two and finds the major aspects between them. Each connection is weighted: a link between personal planets like the Sun, Moon, Venus, Mars and the Ascendant counts for more than a link between slow outer planets, because the personal planets are what you feel day to day.
From those weighted connections it produces a single connection score and a ranked list of the aspects that shape the bond. Tap any connection to read the logic behind it. Nothing here is generic. Every line is built from the two real charts, with the reasoning shown, so you can learn the craft as you go rather than just take a verdict on faith.
The five aspects that shape every connection
An aspect is simply the angle between two planets. Five of them carry most of the meaning in a relationship. Here is what each one does.
Two planets sit together and merge. Their energies fuse, for better or worse, intensifying whatever they touch.
An easy opportunity. The two planets cooperate when you make a little effort, like a door left open.
Friction that forces growth. The planets pull against each other and create the productive challenges a relationship grows through.
Natural harmony. The energies flow together without effort, the gifts a couple shares from day one.
A face-off and an attraction. Opposite planets both repel and complete each other, the classic "opposites attract".
The planets that matter most between two people
Not every planet weighs the same in love. These six do the heavy lifting, which is why the calculator gives their connections more weight.
Core identity and ego. Sun connections show whether you see and celebrate who the other person truly is.
Emotions and comfort. Moon links govern how safe and understood you feel together at home, behind closed doors.
Love, affection and values. Venus is the headline planet of attraction and what you each find beautiful and worth keeping.
Drive, passion and conflict. Mars contacts spark desire and also reveal how you fight and make up.
Communication. Mercury aspects show whether you simply get each other in conversation, or constantly talk past one another.
First impressions and chemistry. The Ascendant shapes the instant pull, the way you read each other on sight.
Element compatibility: fire, earth, air, water
Every sign belongs to one of four elements, and the elements are a fast first read on how two people mesh. As a rule, fire and air feed each other, while earth and water nourish each other. Same-element pairs share a language; opposite temperaments can either balance or frustrate. It is a starting point, not the whole story, because the full chart always has the final word.
Bold, passionate and quick to act.
Grounded, loyal and practical.
Curious, social and idea-driven.
Deep, intuitive and emotional.
What your compatibility score means, and what it does not
The score is a friendly summary of how the two charts interact, not a verdict on whether a relationship will last. A high score means many easy, supportive contacts; a lower score means more friction, which is not the same as doom. Some of the most enduring couples have charts full of squares, because friction creates the spark and the growth that keeps two people interested for decades.
Read the score as a conversation starter. Astrology describes tendencies and dynamics, the weather of a relationship, while the choices always stay with the two people in it. Use the connections below your score to understand each other, not to decide each other.
How to get the most accurate result
Birth dates alone reveal a great deal: your Sun, Mercury, Venus, Mars and the outer planets are all reliable from the date. To sharpen the reading, add each person's birth time and city. The time fixes the fast-moving Moon precisely and unlocks the Rising sign and the houses, which is where chemistry and daily life really live. If you do not know a birth time, run the date-only reading first, then refine it later.
Zodiac compatibility by sign
New to the signs? Start with each one's strengths, needs and quirks, then run any two charts together in the calculator above for the full picture.
Compatibility questions, answered
Synastry compares two birth charts and looks at the aspects (angles) between one person’s planets and the other’s. Those connections describe how two people’s energies interact: where there is ease, where there is friction, and what each person brings out in the other.
No. Birth dates alone reveal most planet connections (Sun, Mercury, Venus, Mars and more). Adding each person’s birth time and city sharpens the fast-moving Moon and unlocks the Rising sign and houses, which makes the reading more precise.
No. The score is a friendly summary of how the two charts interact, not a prediction. Astrology describes dynamics and tendencies, while the choices always stay with the people involved. A lower score simply means more friction, which many lasting couples thrive on.
Yes. Sharing a Sun sign can feel familiar and easy, but real compatibility comes from the whole chart. Two people of the same sign can still have very different Moons, Venus and Mars placements, which is where the deeper connection is decided.
As a quick guide, fire signs (Aries, Leo, Sagittarius) flow with air signs (Gemini, Libra, Aquarius), and earth signs (Taurus, Virgo, Capricorn) pair well with water signs (Cancer, Scorpio, Pisces). Same-element pairs share a natural language. The full synastry above always refines this first impression.
Yes, completely free, with no sign-up required. Enter two birth dates to get a connection score and the key aspects between the charts, each explained in plain English.