Placidus vs Whole Sign Houses: What Actually Changes?

Placidus and Whole Sign are different ways of dividing a chart into houses. Switching between them does not move the planets in the sky; it changes how their zodiac positions are assigned to areas of life.

Whole Sign houses

The entire rising sign becomes the first house. The next sign becomes the second house, continuing in zodiac order. Every house begins at zero degrees of a sign.

Placidus houses

Placidus is a time-based quadrant system. The Ascendant and Midheaven anchor the chart, while intermediate cusps are calculated from apparent daily motion. Houses can have unequal zodiac spans. At high latitudes, some cusps can become highly compressed or difficult to calculate.

Why a placement appears to move

A planet keeps the same zodiac degree when the house system changes. Only the house boundary changes, so the planet may receive a different house number.

How to compare responsibly

Generate both versions with identical birth data and zodiac mode. Note only the placements whose house changes, and do not combine house numbers from one system with cusps from the other. Pull My Chart defaults to Placidus and offers Whole Sign on the natal form.

Compare both systems · Calculation methodology · Birth-time accuracy

How to compare Placidus and Whole Sign houses

  1. Keep the input fixed: Use the same birth date, exact time, location, and zodiac mode for both charts.
  2. Generate both house systems: Calculate one chart with Placidus houses, then change only the house system to Whole Sign and calculate again.
  3. Compare the house labels: Record only the planets whose house numbers change. Their zodiac degrees do not move when the house system changes.