House Systems
Switch between six house systems in one click — Placidus, Koch, Regiomontanus, Porphyry, Equal and Whole-Sign.
ChartVault supports six house systems, so the chart follows your tradition rather than forcing one on you.
Switch the house system
- Per chart: change the system from within an open chart and the cusps, house numbers and every house-dependent panel redraw instantly.
- App-wide default: set your preferred system in Settings so every new chart opens the way you work.
The six systems
| System | Type |
|---|---|
| Placidus | Time-based, the modern default |
| Koch | Time-based, birthplace-oriented |
| Regiomontanus | Space-based, classical |
| Porphyry | Ecliptic-trisection, simple and old |
| Equal | 30° houses from the Ascendant |
| Whole-Sign | Each sign is a house — the Hellenistic standard |
ChartVault computes Placidus cusps from first principles (trisecting the semi-arcs), and the house numbers sit at each house's true midpoint — so even with unequal houses, the labels are always in the right place.
Near the poles
Placidus and other time-based systems are undefined at extreme latitudes. When a birth place is too far north or south for a valid Placidus solution, ChartVault falls back to Whole-Sign automatically so you still get a usable chart.
What changes when you switch
The house cusps move, every planet's house placement updates, and the panels that depend on houses — profection, dignities, points — recompute. The planets' signs and degrees do not change; only the house framework does.