Kua Number Calculator · lucky directions.
Your personal Kua number under the Eight Mansions school — and the four directions that nourish you, plus the four that drain. Used for orientation: where you sit, where your bed faces, where you set up your desk.
Your Kua appears here.
Enter your birth date and sex, then compute. Your Kua number, life group, element, and four good + four bad directions will appear in this panel.
How we compute this
◆ The methodFind your Ba Zi year
The Kua is reckoned from the solar year, which turns at Li Chun (立春, ~4 February) and not at midnight on 1 January. A birth in January or early February therefore belongs to the previous Kua year — which is why this calculator asks for your full birth date rather than the year alone.
Born 15 Jan 1990 → Ba Zi year 1989Reduce that year
Sum the four digits of your Ba Zi year, then reduce to a single digit. Master numbers 11 and 22 are not preserved in Eight Mansions — only single-digit Kua numbers map to trigrams.
2002 → 2 + 0 + 0 + 2 = 4Apply the sex offset
Eight Mansions uses a different formula for men and women, derived from the He Tu / Lo Shu pairing. Post-2000 births use a revised lookup from classical texts.
F (pre-2000): (10 − year_sum) mod 9, 0 → 9 M (pre-2000): (year_sum − 1) mod 9, 0 → 9Map to trigram + group
Each Kua maps to one of eight trigrams and one of two groups — East (1, 3, 4, 9) or West (2, 6, 7, 8). The four good and four bad directions follow from the trigram’s relationships.
Kua 4 → Xun (☴) → East groupThis same date, in other systems
◆ Cross-referenceTerms used on this page
This is one of nine systems.
Your Kua tells you where to sit. Your Ba Zi tells you when to act. Your Human Design tells you how to decide. Get the synthesis — your full blueprint, free.