What synastry calculates
Synastry measures the angular separation between a placement in one natal chart and a placement in another. The closer that separation is to a major aspect angle, the louder the contact.
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FREE SYNASTRY CHART
Synastry shows where two charts make contact.
Read conjunctions, sextiles, squares, trines, and oppositions between two natal charts in plain language—without turning people into a pass/fail test.
Calculate mine free No signup · private by defaultRUN THE ACTUAL CALCULATION
The tool lives on this page.
Enter the birth details once. The same tested engine calculates the full chart, then the result opens the focused layer described above. No email gate, no placeholder result, and no guessed birth time.
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- Timezone-normalized birth instant
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- Sun through Pluto + chart angles
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- Private result with evidence
THE USEFUL VERSION
What this tells you—and what it doesn’t.
What an orb means
The orb is the difference between the observed separation and the exact aspect. A 0.5° square is more exact than a 5° square; exactness describes signal strength, not whether it is good or bad.
What it cannot decide
A chart comparison cannot measure consent, communication skills, shared values, safety, timing, or the work two people are willing to do. Those remain more important than symbolism.
CLEAR ANSWERS
Before you calculate.
Which aspects matter most?
Tight contacts involving the Sun, Moon, Mercury, Venus, Mars, Saturn, and angles are usually the most immediately personal. The full pattern matters more than one aspect.
Are squares and oppositions bad?
No. They often describe difference, pressure, and awareness. That can become conflict, attraction, motivation, or growth depending on how people handle it.
Is synastry different from a composite chart?
Yes. Synastry compares two natal charts directly. A composite chart mathematically creates a third chart from the midpoints between them.
NO MORE GENERIC HOROSCOPES