Love Compatibility & Synastry
Real astrological compatibility goes far beyond Sun signs. Enter two birthdays and Barry compares both full charts: every planet-to-planet aspect between you, Venus and Mars chemistry, emotional bonds, house overlays and your composite “relationship chart”.
Astrology compatibility is for fun and reflection. Every relationship is unique, and love is built by the two of you.
How this free synastry calculator works
Synastry is the astrology of relationships. Instead of matching two Sun signs, it lays one person’s birth chart over the other’s and looks at how every planet of one touches every planet of the other. Barry calculates both charts with real astronomy, finds every aspect between them and turns them into a compatibility score and a full written reading. It is free, with no sign-up, and works for partners, crushes, friends and family.
What your compatibility report includes
- An overall compatibility score plus five areas: attraction & chemistry, emotional bond, communication, long-term commitment, and fun & growth.
- A bi-wheel with both charts on one wheel and the aspect lines between you.
- Your strongest bonds and growth edges: the most important harmonious and challenging synastry aspects, each explained.
- Planet by planet: how your Suns, Moons, Mercurys, Venuses, Marses, Jupiters and Saturns compare.
- Venus–Mars chemistry and Moon–Moon emotional rhythm.
- House overlays: which areas of life each of you activates for the other (needs birth times).
- Your composite chart: the midpoint Sun, Moon, Mercury, Venus and Mars that describe the relationship itself.
- Every synastry aspect with its orb, plus Barry’s tip for your lowest-scoring area.
The synastry aspects that matter most in love
- Sun–Moon: the classic marriage aspect, when one partner’s identity nurtures the other’s emotions.
- Venus–Mars: romantic and physical attraction.
- Moon–Moon and Moon–Venus: emotional ease and tenderness in daily life.
- Mercury contacts: how easily you talk, joke and solve problems.
- Saturn contacts: the commitment glue of long-lasting relationships, sometimes with weight and responsibility.
- Ascendant contacts: instant recognition and first-sight attraction.
Synastry vs zodiac sign compatibility
Sun-sign compatibility only compares one planet out of ten, so two people with “incompatible” signs can still have a deep connection through their Moons, Venuses or Saturns. That is why full synastry is far more accurate. If you only know each other’s signs, you can still try the quick match above.
Love compatibility FAQ
Is this love compatibility calculator free?
Yes. The full synastry report, composite chart and quick sign match are completely free, with no account or email.
Do we need our birth times?
No. Birth dates alone give you every planet-to-planet aspect and the compatibility scores. Adding birth times and cities unlocks house overlays and Ascendant contacts.
What is a good compatibility score?
Most couples score between 55% and 85%. Above 75% shows a strong, natural match, but a lower score is not a bad sign: challenging aspects often bring passion and growth.
What is the difference between synastry and a composite chart?
Synastry compares two separate charts to show how you affect each other. A composite chart blends them into one, using the midpoint of each pair of planets, to describe the relationship as its own entity.
Are squares and oppositions bad in synastry?
Not at all. Hard aspects create friction, attraction and growth. Many lasting couples have strong squares and oppositions; they show where patience and communication matter.
Can I check compatibility with just our zodiac signs?
Yes. Use the quick match link in the form to compare two Sun signs instantly, then add your birthdays for the full reading.
Keep exploring
Free birth chart calculator · Weekly horoscope · Daily love tarot · Numerology · Zodiac gifts · All free readings
