How zodiac compatibility is worked out
Everything starts from distance. Number the signs from Aries (1) to Pisces (12) and count how many signs apart two of them are, going the short way around the circle. Each step is 30 degrees, and the distance gives the aspect astrologers use: 0 is the same sign, 1 a semi-sextile, 2 a sextile, 3 a square, 4 a trine, 5 a quincunx, 6 an opposition.
Take Aries and Scorpio. Aries is sign 1 and Scorpio is sign 8, so they are seven signs apart one way and five the other. Five steps make 150 degrees, a quincunx. That one number explains most of what is written about the pair: the two signs share no element (fire and water) and no quality (cardinal and fixed). What they do share is a ruling planet, Mars, which the calculator also checks.
The element and the quality follow from the distance. Signs four apart are always the same element, signs three apart always the same quality, and signs two apart pair fire with air or earth with water, the two element pairs the tradition calls friendly. That is why a compatibility chart has a repeating pattern instead of 78 unrelated verdicts.
Zodiac compatibility chart
Find your sign in a row and the other sign in a column. The symbol is the aspect between them; the color tells you how the tradition reads it.
| ♈︎Aries | ♉︎Taurus | ♊︎Gemini | ♋︎Cancer | ♌︎Leo | ♍︎Virgo | ♎︎Libra | ♏︎Scorpio | ♐︎Sagittarius | ♑︎Capricorn | ♒︎Aquarius | ♓︎Pisces | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ♈︎ Aries | = | · | ✱ | □ | △ | ᐯ | ☍ | ᐯ | △ | □ | ✱ | · |
| ♉︎ Taurus | · | = | · | ✱ | □ | △ | ᐯ | ☍ | ᐯ | △ | □ | ✱ |
| ♊︎ Gemini | ✱ | · | = | · | ✱ | □ | △ | ᐯ | ☍ | ᐯ | △ | □ |
| ♋︎ Cancer | □ | ✱ | · | = | · | ✱ | □ | △ | ᐯ | ☍ | ᐯ | △ |
| ♌︎ Leo | △ | □ | ✱ | · | = | · | ✱ | □ | △ | ᐯ | ☍ | ᐯ |
| ♍︎ Virgo | ᐯ | △ | □ | ✱ | · | = | · | ✱ | □ | △ | ᐯ | ☍ |
| ♎︎ Libra | ☍ | ᐯ | △ | □ | ✱ | · | = | · | ✱ | □ | △ | ᐯ |
| ♏︎ Scorpio | ᐯ | ☍ | ᐯ | △ | □ | ✱ | · | = | · | ✱ | □ | △ |
| ♐︎ Sagittarius | △ | ᐯ | ☍ | ᐯ | △ | □ | ✱ | · | = | · | ✱ | □ |
| ♑︎ Capricorn | □ | △ | ᐯ | ☍ | ᐯ | △ | □ | ✱ | · | = | · | ✱ |
| ♒︎ Aquarius | ✱ | □ | △ | ᐯ | ☍ | ᐯ | △ | □ | ✱ | · | = | · |
| ♓︎ Pisces | · | ✱ | □ | △ | ᐯ | ☍ | ᐯ | △ | □ | ✱ | · | = |
Green: easy (same sign, sextile ✱, trine △). Red: charged (square □, opposition ☍). Violet: needs adjusting (neighbors ·, quincunx ᐯ). Linked symbols open the page for that pair; the other pairs are covered by the calculator until their pages are written.
The seven ways two signs can relate
Here is what each distance is said to bring, with how often two random birth dates from our count of 35,064 land on it.
| Apart | Aspect | Share of random pairs | How it is read |
|---|---|---|---|
| 0 | Same sign | 8.3% | Instant recognition. You share strengths and blind spots, and nobody covers the other's weak side. |
| 1 | Semi-sextile, neighbors | 16.7% | Signs side by side, with no element or quality in common. Attraction is often slow to start; each partner shows the other a different way of doing things. |
| 2 | Sextile | 16.7% | Friendly elements. An easy friendship that tends to deepen; the spark grows with time rather than arriving all at once. |
| 3 | Square | 16.7% | Same quality, clashing elements. Two people who both want to lead, hold on, or change course, in different ways. High chemistry and real arguments. |
| 4 | Trine | 16.7% | Same element, the classic good match. Things flow; the usual warning is that comfort can turn into taking each other for granted. |
| 5 | Quincunx | 16.7% | Nothing in common by element or quality. A pair that keeps adjusting, often fascinated by how differently the other one works. |
| 6 | Opposition | 8.3% | Opposite ends of one axis, such as Leo and Aquarius. Strong pull and regular tug-of-war; each has what the other lacks. |
The shares come straight from the geometry: each sign is about one-twelfth of all birthdays (between 8.1% and 8.6% in our count), every sign has two neighbors, two sextiles, two squares, two trines and two quincunxes, but only one same sign and one opposite. Easy Sun pairs add up to 41.7%, charged ones to 25%, and the pairs that need adjusting to 33.3%.
Most compatible and least compatible signs
The pairs astrology calls the most compatible are trines: Aries with Leo and Sagittarius, Taurus with Virgo and Capricorn, Gemini with Libra and Aquarius, Cancer with Scorpio and Pisces. Same element means the same basic temperament, so less has to be explained. Sextiles come next, pairs like Aries and Gemini or Cancer and Virgo.
The least compatible, by the same logic, are squares, where the elements clash, and quincunxes, where element and quality both differ: Aries and Cancer or Taurus and Leo for the first, Aries and Scorpio or Gemini and Scorpio for the second. Read "least compatible" carefully. It means the two styles need more translation, and compatibility grids usually add that a square pair can have the strongest attraction of all. In our count, half of all random pairs come from elements with nothing in common, so if your Suns clash you are in very ordinary company.
Why your birth date says more than your sign
Your Sun sign is one planet out of several. For love, astrologers compare at least four: the Sun for personality, the Moon for feelings and home life, Venus for what you find lovable, and Mars for desire, pace and temper. The classic test of attraction is one partner's Venus against the other's Mars, checked both ways. A date of birth gives all four (the Moon sometimes needs the time as well).
Our count shows how much this changes the picture. Across all random pairs, 65.8 in 100 have at least one easy Venus–Mars link. For pairs whose Suns are in a trine or sextile the figure is 67; for pairs whose Suns square, oppose, quincunx or sit next to each other it is 65, almost the same. Put differently, 37.9 in every 100 couples have Sun signs in one of those four positions and a Venus–Mars link the charts call easy. Sun-sign compatibility alone cannot tell you which group you are in; the calculator can.
The pair matters, but less than you might think. Every one of the 78 sign pairs lands between 60 and 73 in 100. Aries and Scorpio sit near the bottom at 60.5 (number 71 of 78), in a group made up entirely of quincunx and opposite pairs, all between 60 and 61. At the top are same-sign and neighbor pairs, such as two Virgos or Leo with Virgo, at about 72, because both partners' Venus tends to fall in the same few signs.
Why compatibility percentages disagree
Aries and Scorpio show the problem. On October 13, 2026, zodiacsign.com scored this one pair at 48%, asknebula.com at 60%, indastro.com at 70% and timesofindia.com at 75%, while mysticmag.com gave it 6.5 out of 10. None of them shows how the number was made. Astrology itself has no such scale. What it has is the set of angles above, read one by one: an easy link here, a tense one there.
We do print numbers, but they mean something you can check: how many random pairs out of 100 share your configuration, counted over every birth date from 1930 to 2025. That is a frequency, not a grade, and it is the same for a happy couple and an unhappy one.
Questions about zodiac compatibility
Which zodiac signs are most compatible?
By the usual reading, signs of the same element: Aries, Leo and Sagittarius among the fire signs, Taurus, Virgo and Capricorn among earth, Gemini, Libra and Aquarius among air, Cancer, Scorpio and Pisces among water. Next come sextile pairs, where fire meets air or earth meets water. A same-element pair is the easiest one to start, which says nothing about whether it lasts.
What two signs do not go together?
Astrology has no pair that cannot work. The pairs it calls hardest are squares (three signs apart, such as Aries and Cancer), whose elements clash, and quincunxes (five apart, such as Aries and Scorpio), which share neither element nor quality. In our count, 50 of every 100 random pairs are from elements with no common ground, so a "hard" Sun pair is the normal case.
Is there a zodiac compatibility percentage?
Not in the astrological tradition. Sites that print a percentage use their own scoring, which is why one pair gets 48% on one site and 75% on another. Our calculator shows what the tradition actually compares, the angles between your planets, and how often a pair like yours occurs.
How do I check compatibility by birthday?
Enter both birth dates in the calculator above. It finds the Sun, Moon, Venus and Mars of each person for that day, then compares eight pairs of planets by sign and by exact degree. The birth time is optional; it matters mostly for the Moon.
Does the Moon sign or Venus sign matter more than the Sun sign?
For love, astrologers usually weigh Venus, Mars and the Moon at least as much as the Sun. Venus describes what you find lovable, Mars what you desire and how you fight, the Moon what makes you feel at home. Two Aries–Scorpio couples can have completely different Venus and Mars links.
Can I check friendship compatibility the same way?
Yes. The same angles apply; for friendship astrologers look mostly at the Sun, Moon and Mercury, and less at the Venus–Mars links, which are read as romantic and physical attraction.
What about big three compatibility (Sun, Moon, rising)?
The rising sign needs an exact birth time and place, which this calculator does not ask for. It does compare the Sun and Moon, and adds Venus and Mars, which a date alone can give.
How accurate is zodiac compatibility?
The planet positions are exact: our ephemeris is checked to under one arcminute against published sign changes. The meaning of each angle comes from astrological tradition, not from research on couples, so read the result as a description of styles to talk about, not as a verdict.
Sources
- Astronomy Engine: the open-source ephemeris library behind our planet positions, dates and statistics
- How we create our readings: our own calculation of sign dates, positions and the 1930 to 2025 statistics
Written by The Zodiac Atlas editorial team with the help of AI and edited by a person. Planet positions come from the astronomy-engine ephemeris (tropical zodiac); shares come from our own run of all 35,064 birth dates from January 1, 1930 to December 31, 2025, with two dates paired at random. Astrology is a symbolic tradition, not a science. For numerology, see life path compatibility on our sister site.