What this composite calculates
A midpoint composite is a constructed chart. For each planet, this tool takes the midpoint between its two natal tropical longitudes along the shorter zodiac arc. The same midpoint rule gives the composite Midheaven from the natal Midheavens. These positions can never be read as the sky at one real birth instant. An exact opposition has two equally short midpoints, so the calculator shows both candidates instead of choosing one silently.
For houses, this page uses the reference-place method: the composite MC fixes a sidereal orientation, then the chosen reference latitude and house system determine the Ascendant and cusps. The calculator solves a temporary clock orientation near the halfway birth date only to reuse the site's house engine. That virtual clock is not a third person's birth time and its planetary positions are discarded. A different latitude or house system can change the houses without changing composite planetary longitudes.
This differs from the alternative midpoint house method, which averages corresponding natal angles and cusps. It also differs from a Davison chart, which computes an actual sky at a midpoint instant and place. Exact degrees can vary between calculators because ephemerides, obliquity models, and cusp conventions differ. Confirm both records before drawing conclusions from a near-cusp position.
Astrology is interpretive. A composite offers a way to compare symbols, not a compatibility score, a diagnosis, or evidence of consent or safety. Relationships are understood through the people involved and what they do, not through a wheel.
Compare synastry → · Calculate a Davison chart → · Read relationship-chart methods →