Kua Number Calculator

How the Kua number is calculated

The Kua number (命卦, also written Gua) comes from your birth year and, traditionally, your gender. It links you to one of the eight trigrams and to either the East group or the West group. It is separate from your BaZi (Four Pillars) chart, which uses your full birth moment.

1. Find your year by the Start of Spring. The Eight Mansions year begins at the Start of Spring (立春), around February 4, not on January 1 or at Chinese New Year. If you were born in January or early February, use the previous year.
2. Apply the formula. Take the year modulo 9 (y mod 9). For men: (11 − y mod 9) mod 9. For women: (y mod 9 + 4) mod 9. A result of 0 counts as 9.
3. Replace 5. There is no Kua 5 in the Eight Mansions school. By the common convention, 5 becomes 2 for men and 8 for women.

For example, a man born in 1984 has Kua 7 (West group) and a woman born in 1984 has Kua 8 (West group). Born on the day of the Start of Spring itself? The calculator shows both possibilities and the exact time.

East and West groups

The eight directions

Each Kua number ranks all eight directions. The four supportive ones are Sheng Qi (生气, success and vitality), Tian Yi (天医, rest and well-being), Yan Nian (延年, relationships) and Fu Wei (伏位, stability). The four challenging ones are Huo Hai (祸害), Wu Gui (五鬼), Liu Sha (六煞) and Jue Ming (绝命). A common way to use them: face your Sheng Qi direction at your desk and point your headboard toward Tian Yi or Yan Nian.

This is a traditional framework for thinking about your space, not a rule you must follow.