Composite chart calculator: the relationship as one chart

A composite chart is built by taking the midpoint of each pair of planets in two birth charts: your Sun and theirs make a composite Sun, your Moon and theirs a composite Moon, and so on. The result is read as though it were the chart of a third thing — the relationship itself, rather than either of the two people in it.

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Composite Reports

Experience the essence of your relationship through a composite chart, crafted from the midpoints of each individual's planetary positions. Dive into the heart of your bond, unveiling the nuances of love, friendship, business, romance, and spiritual connections.

Name

Birth date

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Hour Min

City of Birth. Start typing and matching places will appear. For "San Francisco" in the US, type "san". If your city doesn't show up, add the country or state. For example, for "San Francisco" in the Philippines, type "san francisco phil"

Partner's Name

Birth date

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Hour Min

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It is an abstraction, and an honest reading of it starts by saying so. No sky ever looked like a composite: it has no moment and no place, which is why it cannot have a birthday, and why its houses are equal divisions measured from a composite Ascendant rather than the houses of any real horizon. None of that makes it useless — astrologers have read composites for fifty years because they work — but it is why a Davison chart, cast for the midpoint in time and space between two births, is the better chart to transit.

Read the composite Sun first: it says what the relationship is FOR, the thing the two of you keep doing together whether or not you ever named it. Then the composite Moon, which is how the relationship feels from inside, and the composite Ascendant, which is how it looks to everyone else — often startlingly different from how it feels.

The aspects inside a composite belong to the relationship rather than to either person. A composite Venus square Saturn describes an affection that keeps meeting a limit, and both people will recognise it even if neither has that aspect natally. This is the part of the composite that outperforms its own construction, and the reason it survived the objection in the paragraph above.

Both birth times matter, for the usual reason and one more. The planets are fine without them, so the composite Sun, Venus and Mars are trustworthy; the composite Moon can be out by degrees, and the composite Ascendant and houses are unavailable. Since the Ascendant is what the whole house system is measured from here, one unknown time costs more in a composite than in a single chart.

Read it beside the synastry, not instead of it. Synastry says how two people land on each other; the composite says what the two of them together become. Where the two agree you can rely on what you are seeing, and where they disagree the interesting question is usually which of the two the pair actually live in.

A relationship chart describes a relationship; it does not grade one. There is no compatibility score here, because a chart cannot tell two people whether to stay — it can tell them what they will keep meeting, which is something they can work with.

Questions people ask

What is a composite chart?

One chart built from the midpoints of two birth charts, read as the chart of the relationship rather than of either person. Your Sun and theirs make a composite Sun, and so on through both charts.

Composite or Davison chart?

A composite is an average and has no moment; a Davison is cast for the midpoint in time and space between two births and is a chart of something that really happened. Read both: the composite is usually nearer the feel of a relationship, the Davison nearer its timing, and only the Davison can be transited or progressed honestly.

Can a composite chart be transited?

It is done, and this site offers it as the relationship forecast. Be aware of what you are reading, though: the composite houses are equal slices from a midpoint Ascendant, so a transit through its seventh house means less than the same transit through the seventh of a Davison chart.

Do we both need a known birth time?

For the planets, no. For the composite Moon to be exact, and for the Ascendant and the houses at all, yes — and here the Ascendant matters more than usual, because every house in the chart is measured from it.

Is a composite chart the same as compatibility?

No. It describes what a relationship is like, not how good a match two people are. Nobody has ever produced a compatibility score that survives contact with real couples, and this calculator does not pretend otherwise.