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House System Comparator

Different house systems divide the sky differently. Most astrologers default to Placidus, but Whole Sign, Koch, Equal, and nine other systems each produce a distinct set of house cusps -- and can move planets from one house to another. Enter your birth data to see exactly what changes and what stays the same.

All 12 supported systems use the same astronomical positions (DE441 ephemeris). Only the mathematical method of dividing the ecliptic into 12 sectors changes.

Birth data

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I know the precise birth time

House systems to compare

Select up to 4 systems. Placidus is always shown as baseline.

Quick presets:

Your birth data is used only for this calculation and is not stored.

Astronomical positions calculated with NASA JPL DE441 ephemeris.

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