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Sexual Compatibility by Birth Chart

Calculation is kept separate from interpretation · No fatalism, no guaranteed outcomes

Two birth dates, and you see the Sun, Moon, Venus, Mars and Ascendant of both, the tightest contacts between the charts with their orbs, and the four combinations that carry attraction. No percentages and no scores: there is nothing honest to compute them from.

Your partner's data is never stored and never leaves this page

The points, briefly

What Venus, Mars, the Moon and the 8th house mean in synastry

Four definitions the whole page rests on. Read them once and the rest of the texts need no glossary.

Synastry is two charts laid on one circle: a contact appears wherever two people's points stand close together.

Mars in synastry: Mars in synastry shows initiative and pace: who makes the first move, how directly, how quickly it cools, and what irritation looks like. One person's Mars touching the other's Venus is the most common source of what people call attraction: the drive of one lands exactly on what reaches the other. Mars with Mars answers a different question — whether the two of you run at the same speed.
Venus in synastry: Venus covers what reaches a person and what they read as a sign of interest: a word, a repetition, a touch, time itself. It also carries self-worth — how entitled someone feels to want things. In a pair Venus matters less on its own than in whether the other person's behaviour lands on it.
The Moon in synastry: The Moon is need and the way someone recovers: one has to talk it out, the other has to go quiet. In a pair it decides not the beginning but the continuation — trust, separateness, resentment. A shared Moon is barely noticeable in the first weeks and becomes the main thing a year in.
The 8th house in a birth chart: The eighth house is traditionally tied to closeness, depth and what two people show nobody else. It can only be computed when both birth times are known: without a time there are no houses at all, and a calculator that shows them anyway is showing an invention. House overlays belong to the full reading, not to this page.

By zodiac sign

Zodiac sign compatibility — a table by element

This is what "compatibility by zodiac sign" actually means — the coarsest layer there is. It describes shared character rather than attraction, and we show it honestly: ten combinations of elements, each with its own strength and its own cost. Venus and Mars say far more about attraction.

Fire × FireAries, Leo, Sagittarius

Flames in the open wind

Two fiery Suns create a dynamic where neither wants to stand still. Your shared character is built on initiative, brightness, and directness, with each charging the other. You live at a high pace and appreciate having someone equally fast-moving by your side.

The weak spot is competition: two people used to leading rarely know how to yield first. The Sun sets the shared pace of life here, not the attraction — read that in Venus and Mars below.

Fire × EarthAries, Leo, Sagittarius · Taurus, Virgo, Capricorn

Heat meets steady ground

One of you wants to act immediately and live at high speed, while the other values thoroughness, habit, and time. Your connection holds together because fire provides the impulse and warmth, while earth ensures that impulse is grounded into long-lasting results.

The argument is usually the same one: “too slow” against “too abrupt”. Few pairs finish what they start as reliably. On attraction the Sun says nothing: see Venus and Mars.

Fire × AirAries, Leo, Sagittarius · Gemini, Libra, Aquarius

Wind feeding the flame

Combining airy and fiery Suns creates a dynamic that constantly pushes forward. One brings concepts and words, while the other quickly turns them into decisive action. You easily inspire each other and rarely settle, maintaining a very high pace in everything you do.

The weak spot is finishing: there are more ideas and impulses than patience. The Sun shows the pair’s shared rhythm, not its desire; read that in Venus and Mars.

Fire × WaterAries, Leo, Sagittarius · Cancer, Scorpio, Pisces

Boiling water and steam

Fire acts quickly and openly, while water reacts deeply, keeping much hidden inside. Your connection is full of contrasts, with directness meeting subtle moods. When these forces align, the bond is unusually warm, but one often must learn gentleness while the other learns directness.

Arguments flare fast and cool unevenly: one has already forgotten, the other is still hurting. That is the character of the pair, not its pull — for the pull, look to Venus and Mars.

Earth × EarthTaurus, Virgo, Capricorn

Solid ground beneath you

Having an earthy Sun in both charts makes your dynamic solid, predictable, and strongly oriented toward reality. You equally value what can be built, preserved, and physically touched. Attention here is measured not by grand gestures, but by reliability and shared time.

The risk is freezing into a comfortable routine and no longer surprising each other. The Sun describes how you live together, not how you are drawn to each other — that is for Venus and Mars.

Earth × AirTaurus, Virgo, Capricorn · Gemini, Libra, Aquarius

Meaning meets solid ground

One of you looks to the future and seeks new ideas, while the other relies on things that can be touched and tested by time. Your dynamic is built on balancing airy lightness with earthy substance. At its best, one invents and the other brings it to life.

Friction appears when an idea looks empty to one and a demand for results feels like pressure to the other. That is the pair’s character; attraction is not described by the Sun — see Venus and Mars.

Earth × WaterTaurus, Virgo, Capricorn · Cancer, Scorpio, Pisces

Riverbed for deep waters

Earth provides support and structure, while water fills that structure with life and emotion. Your shared rhythm is built on the fact that one’s practicality becomes a safe shore for the other’s depth. Together, you can create a very warm and protected space.

Hurt rarely gets spoken here: one retreats into tasks, the other into silence. This is the background of the relationship, not its attraction — Venus and Mars speak to that below.

Air × AirGemini, Libra, Aquarius

Conversation as the main fuel

Having the Sun in air signs means that talking, exchanging ideas, and moving forward are your most important shared traits. Your dynamic relies on lightness, a bit of distance, and a deep curiosity about the world around you. Boredom is rare as long as there is something left to discuss.

The danger is talking a feeling through before it has been lived. The Sun sets the style of conversation, not the attraction: for that, go to Venus and Mars below.

Air × WaterGemini, Libra, Aquarius · Cancer, Scorpio, Pisces

Words on deep waters

Your shared background involves constantly trying to translate deep feelings into spoken words. Air values clarity, distance, and intellectual understanding, while water relies on depth, mood, and the unspoken. Together, you learn how to connect logic with emotional experience.

The main gap is “explain it” against “feel it”. This is the pair’s background, not its pull; Venus and Mars speak to that, not the zodiac sign.

Water × WaterCancer, Scorpio, Pisces

One shared deep ocean

Two watery Suns create a dynamic where much is understood without words. You equally value depth, devotion, and safety, relying heavily on mood and intuition. Your shared background can be unusually close, provided you do not drown in unspoken grievances.

The risk is sinking into the unspoken together and waiting for the other to guess. The Sun describes the shared background here, not the attraction: read that in Venus and Mars.

Questions

Common questions about birth chart compatibility

Can compatibility be computed without a birth time?

Yes, and it is the most common case. Without a time the Ascendant is not shown and houses are not computed, and placements are taken at noon. The Moon covers about thirteen degrees a day, so its sign is often unsettled without the hour — those points are marked rather than passed off as exact.

Why is there no compatibility percentage?

Because there is nothing honest to compute one from. Any such number is built from weights its author chose, and it moves the moment those weights are touched. We show the calculation itself — placements and orbs — and explain what it means.

Which matters more for attraction, Venus or Mars?

Neither on its own. What works is the meeting: whether the way one person acts lands on what reaches the other. That is why the page carries two crossings, and they read differently — it can come together one way and not the other.

We are different zodiac signs — is that bad?

The Sun sign is the coarsest layer, and there are no bad combinations in it. There are different ways of investing in something shared, each with its own strength and its own cost. About attraction the Sun sign says almost nothing.

Do you store my partner's data?

No. The calculation runs on the server and is written nowhere — no database, no analytics. Only the Venus and Mars signs reach our statistics, with no dates, coordinates or cities.

How is the full reading different from this page?

Here you get the whole calculation and four key combinations by element. The full reading takes every contact between the charts separately, computes the house overlays and the Jyotish kutas, and lets you ask questions about the finished text.