How to Decode Zodiac Sign Compatibility

The recent boom of interest in astrology can likely be attributed to the fact that we love learning more about ourselves and bolstering our self-awareness. But what we adore just as much (maybe even more sometimes, if we're being honest) is learning about the objects of our affection and whether or not we're destined for a cinematic love story — or at least, a satisfying romp between the sheets. And the planets — specifically your natal chart (or birth chart) — can offer helpful intel.

Here, several planetary factors that can provide insight into your zodiac sign compatibility as well as which sign pairings are the most compatible, the most challenging, and the those that are just hit-or-miss.

These Planets Help Shape Zodiac Sign Compatibility

When considering whether you and a potential or existing partner are going to hit it off, you'll want to compare the following celestial bodies. (To get your natal chart — which contains all this info and can help you determine your astrological compatibility, among many other things — you can consult an astrologer or plug your info into an online service such as astrology.com.)

Your sun signs: Whether you're filling out a dating app profile or buying a pretty new zodiac sign pendant, the sign you identify with is the sign that the sun was moving through at the time of your birth. The sun oversees your self-image, self-esteem, identity, and how you experience confidence. It can also influence your life path.

Your moon signs: The shimmering, mysterious moon is considered your inner emotional compass. It's tied not only to the experiences, people, and material items in life that offer you a sense of security but it also impacts how you connect emotionally with others. That's why it's so helpful for identifying someone who shares your values and how you experience intuition and emotion.

Your Venus Signs: The planet of love, romance, beauty, and money speaks to what you most value in a relationship, how you demonstrate desire, how you attract others, and the way you experience pleasure. It can very much characterize how you behave in any of your social interactions and relationships — romantic or otherwise — and color your love language. For those reasons, it's a key player when looking at zodiac sign compatibility.

Your Mars Signs: Mars, the planet of action, influences the things in life that drive you, your energy, your strength, your inner fire, and yep, your sexual style. Chances are, you want your partner to be on the same (or at least a similar) page in terms of all of those aspects of life, so it's a major planet to look to when determining how well you'll vibe with someone else — in and out of bed.

A big-picture must-know: You'll want to think about how all of these planets interact with one another to really investigate astrological compatibility — not just like with like. For example, your sun might technically be square (the harshest angle — more on that in a sec) your partner's sun, but your Venus signs are trine (the sweetest angle), and your moon signs are conjunct (meaning in the same sign). Harmonious aspects like those can significantly rosy up what might, at first glimpse at sun signs, seem like a problematic picture.

Most Compatible Zodiac Signs

Although the most in-depth look at astrological compatibility will come from looking closely at two people's whole natal charts, you can generally find a natural compatibility between two people whose birth charts display trines between their planets. The trine — which indicates that two signs are four signs apart — is the most supportive, harmonious angle between two signs.

Basically, these are the signs that are in the same element as your sign. A quick refresher on which signs fall where — and are therefore trine one another:

• Fire: Aries, Leo, Sagittarius
• Earth: Taurus, Virgo, Capricorn
• Air: Gemini, Libra, Aquarius
• Water: Cancer, Scorpio, Pisces

You might also consider signs that are sextile yours. These signs are two signs apart and fall under a compatible element. Fire and air are simpatico, as are water and earth. While the relationship isn't as frequently celebrated as the trine, it's considered friendly and easygoing. The signs you're sextile to, based on your sign:

• Aries: Gemini, Aquarius
• Taurus: Cancer, Pisces
• Gemini: Aries, Leo
• Cancer: Taurus, Virgo
• Leo: Gemini, Libra
• Virgo: Cancer, Scorpio
• Libra: Leo, Sagittarius
• Scorpio: Virgo, Capricorn
• Sagittarius: Libra, Aquarius
• Capricorn: Scorpio, Pisces
• Aquarius: Aries, Sagittarius
• Pisces: Taurus, Capricorn

Least Compatible Zodiac Signs

Again, astrologers often warn against jumping to conclusions — positive or negative — based exclusively on your sun sign, but generally speaking, squares can indicate challenges in a relationship. The square occurs between signs that are three signs apart, and it's pretty much the astrological version of clashing or head-butting.

Two signs that are square have the same quality (also referred to as quadruplicities): cardinal, mutable, or fixed. Cardinal signs excel at seeing the big picture but not so much with the details, mutable signs are the most flexible but can also struggle to commit, and fixed signs are resolute on their best day and stubborn as hell on their worst.

Having these traits in common might initially sound like the fast track to compatibility, but in the case of squares, too much of the same energy can spell conflict. The following signs are square one another:

• Aries: Cancer, Capricorn
• Taurus: Leo, Aquarius
• Gemini: Virgo, Pisces
• Cancer: Aries, Libra
• Leo: Scorpio, Taurus
• Virgo: Gemini, Sagittarius
• Libra: Cancer, Capricorn
• Scorpio: Leo, Aquarius
• Sagittarius: Virgo, Pisces
• Capricorn: Aries, Libra
• Aquarius: Taurus, Scorpio
• Pisces: Gemini, Sagittarius

Hit-or-Miss Zodiac Sign Compatibility

If your sun — or any planet — is in the same sign as your partner's, they're conjunct with one another. Although conjunctions can make for too much of the same energy at times, plenty of celeb couples have proven it can work. For example, both Neil Patrick Harris and his husband David Burtka are Geminis. Nick and Vanessa Lachey are both Scorpios — and even share the same birthday (November 9). And although that famous 6.1-carat pink diamond didn't lead to nuptials the first time, fellow Leos Ben Affleck (born August 15) and J.Lo (born July 24) tied the knot in August 2022.

Similarly, having the sun, the moon, or another planet in a sign that's directly opposite your partner's could create a case of yin and yang, in which you're organically balancing one another — or it could make it tough to see eye-to-eye. (Again, it depends on other natal chart details to judge astrological compatibility.)

The following signs are opposite one another:

• Aries and Libra
• Taurus and Scorpio
• Gemini and Sagittarius
• Cancer and Capricorn
• Leo and Aquarius
• Virgo and Pisces

A couple of famous examples of attracted opposites: Cancer Prince William (born June 21) and Capricorn Kate Middleton (born January 9) and Leo Mila Kunis (born August 14) and Aquarius Ashton Kutcher (born February 7).

The Bottom Line on Zodiac Sign Compatibility

Exploring how your sun, moon, Venus, and Mars signs interact with a partner's can offer valuable intel on how you connect or clash. But it's important to bear in mind that these details are just a jumping-off point. There are many other layers to investigate when you're considering astrological compatibility. You'll want to understand how certain birth chart details might mirror, harmonize, or clash with your partner's. (For example, say they have a slew of planets in their 12th house, which makes them super-private, while you have most of yours in the 1st house, which means you wear your heart on your sleeve.) You can also look at how your charts interact when they're overlapped on one another (an area of astrology called synastry). Sound like a lot? It is; that's why it's so helpful to sit down with a pro astrologer who can help you zero in on specifics and offer a high-level overview.

Maressa Brown is a writer and astrologer with more than 15 years of experience. In addition to being Shape's resident astrologer, she contributes to InStyle, Parents, Astrology.com, and more. Follow her Instagram and Twitter at @MaressaSylvie.