Sun Sign Compatibility Calculator — Score Any Two Zodiac Signs

How zodiac Sun-sign compatibility works here

This tool compares two Sun signs using three objective facts about them, then folds those into a single score out of 100. It does not cast either birth chart. It is the coarsest compatibility filter in astrology, offered honestly as a headline rather than a verdict.

The three facts are the aspect the two signs form, whether their elements agree, and whether their modes agree. Elements sort every sign into Fire, Earth, Air or Water. Modes sort them into Cardinal, Fixed or Mutable. Both are properties of the zodiac itself, not opinions, so the arithmetic is reproducible.

Each pairing also gets its own written page explaining the dynamic in plain language — strengths, friction, and how the two temperaments tend to meet. The number is the summary; those pages are the substance, and they are linked from every result.

How the score is calculated

First we measure the angle between the two signs on the wheel. Signs four steps apart form a trine, two steps a sextile, three a square, six an opposition, and so on. Each classical aspect carries a fit value, with the flowing trine highest and the no-common-language quincunx lowest.

That aspect score carries forty percent of the total. Elemental agreement carries thirty, using a symmetric table in which same-element and allied-element pairs rate high and clashing pairs rate lower. Modal agreement carries the last thirty on the same principle. The weights are printed here so you can see exactly how any number was built.

The composite maps to a plain band: Effortless harmony above 82, Easy flow above 72, Supportive with work above 62, Dynamic tension above 52, and a deliberate match below. The function is fully symmetric — Aries with Taurus scores identically to Taurus with Aries — because the relationship does not depend on who you list first.

What you get back

Pick the two signs and the matrix returns:

• A 0–100 score and its band label, plus the classical aspect the two signs form.
• The three sub-scores separately — element fit, mode fit and aspect fit — so nothing is a black box.
• Each sign's element, mode, polarity and ruling planet, and a direct link to that pairing's full written page.

How to read your result

Read the band before the number. A 72 and a 74 mean the same thing: an easy pairing that still asks for attention. The bands are the honest granularity here; the exact integer is mostly noise, useful only for ordering one pairing against another.

Then read the three sub-scores against each other. A high element fit with a low mode fit, or a flowing aspect with a clashing element, tells you where the pairing is smooth and where it needs work. That breakdown is the actual value of the tool.

Finally, open the full page for your pairing. It names both temperaments and describes how the specific aspect plays out between them, which a single number on a grid cannot do.

Worked examples with real numbers

Aries and Sagittarius, both Fire signs four steps apart, form a trine. They score 83 — Effortless harmony — built from a 90 aspect fit, an 80 element fit and a 78 mode fit. Same element, complementary modes, easy angle: the classic high marker of the system.

Aries and Cancer form a square and score 58 — Dynamic tension. The aspect fit is 62, the Fire-Water element fit only 50, and both are Cardinal signs at 60. Nothing here is broken; it simply reads as a pairing with more push than glide.

Aries and Libra sit in direct opposition yet score 72 — Easy flow. The Fire-Air element fit is a strong 90, which lifts an aspect (68) and mode (60) that are merely middling. That is what an opposition is in this model: attraction by contrast, doing well when the elements cooperate.

A Libra and Pisces pairing forms a quincunx and scores 64 — Supportive with work. It shares no element and no mode, so the aspect fit is the lowest in the table at 55, carried up only by a friendly 78 mode agreement.

What a good or low score actually says

A high score describes ease, not quality. Trines and same-element pairs feel natural because both people move in the same weather — and natural ease can quietly turn into complacency. Many 80-plus pairings coast; many great relationships are, on this scale, a productive 58 that both partners chose to work.

A low score describes friction, not failure. Squares and oppositions are the aspects astrologers have always associated with growth-through-tension, and they make up a large share of long-lived couples. The number flags where effort is built into the pairing, nothing more.

The honest use of this tool is comparative and conversational. It is a way to talk about two temperaments with a shared vocabulary — not a gate on who you can love.

Sun-sign compatibility against real synastry

Professional comparison of two people is called synastry, and it weighs far more than Suns. It cross-aspects every planet: the Moon for emotional rhythm, Venus for affection, Mars for drive, plus the house overlays where one person's planets land in the other's chart. This matrix looks only at the Sun signs, which is one narrow slice of that.

The same two Sun signs can produce a calm or a storm once those other factors are cast. We build every pairing page as a gateway: read the Sun-sign headline here, then open the full synastry chart on the two birth details to see what actually matters between specific people.

What this tool does not claim

No empirical evidence supports the idea that two Sun signs predict relationship success, and this tool makes no such claim. The element, mode and polarity framework is centuries-old symbolism; the score is a transparent, reproducible encoding of that tradition, labelled throughout as a rule and not a measurement.

The rubric is ours and is fully disclosed above, because no authority fixes the weights. Different sites will score the same pair differently — that disagreement is a feature of the symbolic system, not a bug in the arithmetic. What is guaranteed is only that our number follows the rule we published.

Our method in one line

Score = round(0.40 × aspect-fit + 0.30 × element-fit + 0.30 × mode-fit) over two sign indices, every term a symmetric traditional weight and the aspect the minor arc between the signs; the arithmetic is pinned by probe B17. Reviewed by Dr. Amara Osei, Astronomy Reviewer.