Synastry

Love Compatibility Calculator

Pick two zodiac signs for an instant free compatibility score — passion, trust, communication, intimacy, longevity — then compare two complete birth charts. Compatibility is not a verdict on love. It is a description of the weather two people make together.

  1. 1. Pick the first sign

    Your own sun sign, or the sign of whoever is asking.

  2. 2. Pick the second sign

    A partner, a friend, a colleague — any of the twelve.

  3. 3. Read the scores

    Eight ratings, the aspect between the signs and what to do about it.

The First Chart

The Second Chart

73

Strong and workable

Leo · Fire  /  Scorpio · Water

90° · Square

The Currents

Passion49%
Trust63%
Longevity65%
Communication77%
Intimacy64%
Shared values74%
Friction56%
Growth52%

Fire meets Water, and neither yields easily. What Leo calls momentum, Scorpio calls noise. Handled honestly, this pairing produces more growth than any easy match ever could.

A printable report with every score, the aspect and the full reading.

Elemental chemistry

Steam. Passionate and volatile — feelings evaporate or scald depending on the hour.

Modality dynamic

Immovable and immovable. Loyalty for life, and a decade-long argument about the same subject.

The aspect

Dynamic tension. Real growth, real grinding — never boring, rarely restful.

What works

  • Household logistics resolve themselves with unusual ease.
  • You defend each other in rooms the other is not in.
  • You give each other permission to rest.

Where it grinds

  • Social appetite differs enough to require an explicit agreement.
  • Repair style: one wants the conversation now, the other needs an hour alone first.
  • Pace: one of you decides in a night, the other in a season.

Behind closed doors

Tenderness outperforms intensity here; the quiet nights are the memorable ones.

The first year

Expect an early rupture that, handled well, becomes the foundation of the whole relationship.

Ten years on

A decade in, this pairing is defined by shared infrastructure — home, work, people you both raised or rescued.

Counsel for this pairing

Schedule the difficult conversation before it schedules itself.

Leo

The solar heart. You were made to be witnessed.

Fixed Fire · ruled by The Sun

In love
Generous, theatrical, loyal. You love out loud or not at all.
Shadow to watch
Needing the room's approval before your own.
Easy: Sagittarius, Aries, AquariusGrowth: Scorpio, Taurus

Scorpio

The house of secrets. You are never afraid of the depth.

Fixed Water · ruled by Pluto

In love
All or nothing. You want the true version of a person or none of them.
Shadow to watch
Control exercised through withheld information.
Easy: Pisces, Cancer, TaurusGrowth: Aquarius, Leo

Full chart synastry

Sun signs are the headline. This compares two complete birth charts — every cross-aspect between the ten bodies and both sets of angles, scored across attraction, communication, warmth, stability and growth, with the house overlays that show where each person changes the other's life.

Person one

Person two

All 78 zodiac pairings

Every sign combination has its own written report: scores, elemental chemistry, what works, where it grinds, the first year and the tenth.

Compatibility questions

Is this love compatibility calculator free?

Yes. Every sign pairing, every score and the full birth-chart synastry comparison are free and need no sign-up.

Which zodiac signs are most compatible?

Signs of the same element, and of complementary elements — fire with air, earth with water — usually share a language most easily. Trines, signs four apart, are the classic easy match; oppositions are magnetic but corrective.

Do I need a birth time for compatibility?

No. Sun-sign compatibility only needs two signs. A birth time unlocks the full synastry comparison, where houses and the ascendant show where each person changes the other's life.

Can a low compatibility score still work?

Yes. A low score describes friction, not failure. Squares and quincunxes ask for translation work, and couples who do it deliberately often outlast the easier matches.

In short

Free love compatibility calculator: pick two zodiac signs for instant scores on passion, trust, communication, intimacy and longevity, plus full birth-chart synastry and 78 sign-pair reports.

  • A high score is not a promise and a low score is not a sentence. Charts describe terrain, not effort.
  • Look at what each chart needs, not only where they match. Compatibility is largely about whether needs collide.
  • Squares between charts create heat. Long relationships often run on one or two of them.
  • Compare the same pair across friendship, work and romance — the same contacts read differently by context.

Synastry — comparing two charts — is documented in Hellenistic sources and became a staple of medieval Arabic astrology, where marriage elections were serious civic business. The technique overlays one chart on another and reads the contacts: where your Venus meets their Mars, where your Saturn lands in their houses.

Modern practice adds the composite chart, a mathematical midpoint of two charts treated as the relationship's own natal map. Between the two you get both the chemistry and the entity the chemistry produces.

Questions Readers Ask

What if I don't know their birth time?

You still get every planetary contact except Moon-precise aspects, the ascendant and the houses. That is enough for a useful reading.

Which contact matters most?

Sun-Moon for ease, Venus-Mars for attraction, Saturn for endurance, and Moon-Moon for whether daily life feels restful.

Can this work for friends and colleagues?

Yes. Read Mercury and Mars contacts for working pairs — communication and drive matter more there than Venus.