Your shared chart
— the astrology of the relationship itself
A composite chart merges two birth charts into a single one — the horoscope of your relationship as its own being. It doesn’t show how you attract each other (that’s synastry); it shows who you ARE together. Free, with a plain-language reading.
The composite chart is the birth chart of your bond — from the midpoint between your two charts.
Person 1 — you
When were you born?
The date sets the Sun, Moon and every planet.
Three steps to your composite
Enter both birth details
Date, place and — if you can — time for both of you. The time makes the shared Ascendant and houses precise.
Compute the midpoints
We calculate the exact midpoint between your two charts for every planet — with the Swiss Ephemeris engine, to the arc-minute.
Read your shared chart
You see the composite Sun, Moon, Ascendant and every planet in sign and house — with a reading.
The basics
What is a composite chart?
A composite chart merges your two birth charts into a single, third chart — the chart of the relationship itself. Not you, not your partner, but the "us" the two of you create together. It shows the character and purpose of the bond as its own living thing.
How it differs from a compatibility check
A compatibility check lays your two charts side by side and looks at where your energies click and where they rub. A composite goes one step further: it builds a brand-new chart from the midpoints of both, describing the relationship as an entity in its own right — with its own Sun, Moon and Ascendant.
What to look at first
The composite Sun is the relationship’s core purpose — what the two of you are here to build. The composite Moon is its emotional home, how safe and nourished you feel together. The composite Ascendant is how you come across as a couple to the outside world.
How a composite chart is calculated
A composite chart takes, for every planet, the midpoint between your position and your partner's. If your Sun is at 10° Aries and theirs at 10° Gemini, the composite Sun sits exactly in between: at 10° Taurus. Planet by planet, a third chart emerges. It belongs to neither of you alone — it describes what grows between you.
| Method | How it is calculated | What it shows |
|---|---|---|
| Synastry | both charts overlaid, angles between the planets | how you affect each other |
| Composite chart | midpoint of every planet pair | character and purpose of the bond |
| Zodiac sign comparison | only the two Sun signs | the quick first impression |
Where to start
- Composite Sun: its sign and house describe what you are together for — building something, seeing the world, giving each other a footing.
- Composite Moon: how safe the “us” feels, for example whether after a long day you would rather talk or sit side by side in silence.
- Composite Ascendant: how others see you as a couple. It needs both birth times.
Read the composite as a question to you both, not a verdict: do you recognise your “us” in it? To see how your individual planets touch, the compatibility chart complements the composite. The houses the composite planets land in are explained by the house calculator.
Composite chart — frequently asked questions
- What is a composite chart?
- A composite merges two birth charts into one by taking the midpoint between both for every planet. The result is the horoscope of your relationship as a being of its own.
- How is it different from a compatibility chart (synastry)?
- A compatibility chart overlays your two charts and shows how you affect each other. The composite turns both into a single new chart — who you are together.
- Do we both need our birth time?
- For the composite planets in the signs, date and place are enough. For the shared Ascendant and houses you both need an accurate time.
- Which points in the composite matter most?
- The composite Sun (the identity of your relationship), the composite Moon (your emotional foundation) and the composite Ascendant (how you come across as a couple). If the composite Sun sits in the seventh house, for example, your relationship turns strongly on partnership and balance itself.
- Does the composite chart change over time?
- No. The composite is built from your two birth charts and stays the same for as long as you both exist. What changes are the transits touching the composite — they show which phase your relationship is moving through.
- Is the composite chart free?
- Yes. You can calculate your composite chart here for free, with no sign-up.
Your relationship as one chart
Two become one
We take the midpoints between your planets — your Sun and their Sun make the composite Sun. The result is a real third chart.
Sun, Moon, Ascendant — together
Where the composite Sun, Moon and Ascendant sit: the identity, the feeling and the face of your relationship.
Houses and aspects
Which life area (house) each shared planet falls in, and which tensions and talents shape your composite.
Explained in plain words
Every placement in everyday language — no jargon, even if you’re brand new to astrology.
Reviewed by Theresa Touhey · Astrologer & Tarot ReaderWho are you together?
Two birth details, one calculation — your composite chart in signs, houses and aspects. Instant, free, with a reading.
Calculate composite chartFree, no sign-up.