House Systems
Compare how different frameworks divide the local sky into 12 Bhavas — from Whole Sign to Placidus.
Cusp Distribution Wheel
Cusp Angles
| House | Cusp | Size |
|---|---|---|
| H1 | 0.0° | 30.0° |
| H2 | 30.0° | 30.0° |
| H3 | 60.0° | 30.0° |
| H4 | 90.0° | 30.0° |
| H5 | 120.0° | 30.0° |
| H6 | 150.0° | 30.0° |
| H7 | 180.0° | 30.0° |
| H8 | 210.0° | 30.0° |
| H9 | 240.0° | 30.0° |
| H10 | 270.0° | 30.0° |
| H11 | 300.0° | 30.0° |
| H12 | 330.0° | 30.0° |
Red = very small house. Blue = very large.
About this system
Rashi Chakra
The entire sign containing the Ascendant becomes House 1. Each subsequent sign is the next house, regardless of degree.
Key distinction
The sign IS the house. ASC degree only determines House 1 start, not house boundaries.
Prerequisites
The Four Angles — The Only Points Every System Agrees On
Every house system divides the sky using the same four anchor points. The disagreement is only about what happens between them.
Ascendant
Degree of ecliptic rising on the eastern horizon at birth. Always House 1 cusp.
Descendant
Opposite the ASC (always 180° away). House 7 cusp.
Midheaven
Highest ecliptic point above the horizon. House 10 cusp.
Imum Coeli
Opposite the MC. Lowest point, below the Earth. House 4 cusp.
Core Concept
Why Do House Systems Disagree?
Houses are local, not universal
Unlike zodiac signs (which depend only on the Sun's annual path), houses depend on where you are on Earth and what time it is. The sky looks completely different from Kolkata vs. Oslo vs. Quito — so the houses are different too.
The quadrants are unequal in arc size
The MC is rarely exactly 90° from the ASC. At high latitudes it can be as little as 40° away, creating highly unequal quadrants. Each system answers "what do we do with this unevenness?" differently.
Three different geometric choices
Ignore the unevenness (Equal / Whole Sign) — simply count 30° from the ASC and move on. Divide the ecliptic arcs equally (Porphyry / Sripati) — split each quadrant into 3 equal arcs. Divide time, not arc (Placidus) — track how long each degree takes to rise and divide that time.
Key insight: Use the latitude slider on the wheel to see how the same system produces very different house sizes depending on your birthplace. At the equator all systems converge. Near the poles, they diverge dramatically.
Bhava Chalit & the Dual-Chart Practice
Most Vedic astrologers use two charts simultaneously:
Rashi Chakra (Sign Chart)
The primary chart. Uses Whole Sign houses. Planets are interpreted in their signs. This is what most people mean when they say "my Vedic chart."
Bhava Chalit (Shifted Chart)
Uses Sripati cusps to re-examine which house a planet truly falls in. A planet near a sign boundary may shift into the previous house. Used for assessing house strength.
Sripati's Unique Contribution
Sripati (11th century) defined the cusp as the Bhava Madhya — the midpoint of a house — not its starting boundary. This means his calculated "cusp" is actually the centre of the house. The Bhava Sandhi (junction) is the true boundary, falling midway between two Bhava Madhyas. This interpretation is fundamentally different from all Western systems.
Parashara's primary recommendation in Brihat Parashara Hora Shastra is the Whole Sign system for sign-based interpretation. Sripati/Porphyry is used as a supplementary lens, not a replacement.
The Math of Houses: Dividing the 3D Sky
How do we divide the sky into 12 Bhavas? The challenge is that we're projecting a 3D sphere onto a flat wheel. The celestial sphere has a horizon, a meridian, an ecliptic, and a celestial equator — all intersecting at different angles. Each house system picks a different one of these circles as its primary reference and divides it differently.
Equal / Whole Sign
Divide the ecliptic. Simple, latitude-independent, historically dominant in India.
Porphyry / Sripati
Divide the ecliptic arcs between angles. Latitude-dependent but geometrically clean.
Placidus
Divide time (the semi-diurnal arc). Astronomically rigorous, but breaks at high latitudes.
Based on sacred traditions. May divine grace be with you.