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House Cusp Calculator

A house cusp marks where one house ends and the next begins. Under the **Whole Sign** system this site uses, that boundary is simple and exact: every house cusp except the 1st falls precisely at 0° of the sign occupying that house, since the whole sign IS the house. Only the 1st house cusp — your **Lagna** — falls at a genuinely precise degree, computed to the minute from your exact birth data.

Ayanamsa: Lahiri (Chitrapaksha) · Houses: Whole Sign · Cusp = the starting degree (bhava madhya) of each house's sign

Don't know your birth time? We'll approximate your chart using 6:00 AM local time. The Lagna (Ascendant) and house positions will be approximate.

Reviewers

Sarah Mitchell, M.A. in Cultural Astronomy & Astrology and Marcus Reynolds, Professional Astrologer & Astronomer

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What a House Cusp Actually Is

In cusp-based Western house systems (like Placidus), every one of the 12 cusps requires its own trigonometric calculation, and houses can vary considerably in size. Whole Sign houses sidestep that entirely: each house is, by definition, exactly one 30° sign, so 11 of the 12 cusps are trivially known the moment the Lagna sign is known — only the Lagna's own cusp needs precise ephemeris math.

Why the Lagna Cusp Is the One Exception

Your Lagna is the exact degree of the eastern horizon at your birth moment — a genuinely continuous value that depends precisely on birth time, date, and location. This calculator reports it to the minute, since it's the one cusp in the Whole Sign system that carries real degree-level information, distinct from every other house's simple 0°-of-sign boundary.

A Note on Honest Precision

Some tools present false precision for houses 2 through 12 by borrowing cusp math from an entirely different house system (like Placidus) and mislabeling it as "Vedic." This calculator states plainly that, under the Whole Sign convention, those 11 cusps are exactly 0° of their sign — no more, no less — rather than manufacturing decimal-degree cusps that don't belong to this system.

House Cusp Calculator FAQs

What is a house cusp?
The boundary degree where one house ends and the next begins — under Whole Sign houses, this is simply 0° of the sign occupying each house, except for the Lagna, which carries a genuinely precise degree.
Why is only the Lagna cusp shown with a precise degree?
Because Whole Sign houses make every other cusp trivially 0° of its sign by definition — only the Lagna, the exact rising degree, is a continuously variable value that needs precise calculation.
Is this the same as a Placidus house cusp calculator?
No — Placidus and other cusp-based systems compute all 12 cusps at unequal, precisely calculated degrees; this calculator reflects the Whole Sign convention used throughout this site, where 11 of 12 cusps are simply the start of their sign.
Why does this site use Whole Sign houses instead of Placidus?
Whole Sign is the house system most classical Parashari Vedic texts assume by default and remains the standard among practicing Vedic (as opposed to Western) astrologers.
Do I need my exact birth time for an accurate house cusp?
Yes — the Lagna cusp is highly time-sensitive, shifting roughly one degree every four minutes, so an accurate birth time is essential for this specific reading.