What is a kua number?

In Eight Mansions feng shui every person gets one life gua from birth year and gender: a number from 1 to 9 — 5 never appears as itself — a trigram, and a group. Kan 1, Zhen 3, Xun 4 and Li 9 form the East group; Kun 2, Qian 6, Dui 7 and Gen 8 form the West group. The group decides which four of the eight directions carry the favorable stars for that person.

Which year boundary does this page use?

The lichun instant, the same boundary this site uses for the year pillar: born before lichun, you count as the previous year. Many kua tables use January 1 or lunar new year instead. Those are different conventions, not errors, and they disagree for births near the boundary — this page computes with lichun and shows the exact instant it compared against.

My remainder is 5 — where is my gua?

Palace 5 belongs to the center and has no trigram, so a remainder of 5 is parked: a male counts as Kun 2, a female as Gen 8. This is the mainstream handling and the result panel marks it explicitly whenever it applies.

Where do the eight direction stars come from?

From the Da You Nian verse, a fixed table every Eight Mansions school shares: from your life gua the seven other directions receive Sheng Qi, Yan Nian, Tian Yi, Huo Hai, Liu Sha, Wu Gui and Jue Ming in a fixed order, and your own palace holds Fu Wei. The full 8 by 8 table is printed below. It is fully symmetric, and the four favorable stars always land on same-group directions — two structural facts you can check row by row.

What do I do with my East or West group?

The classical convention of the Eight Mansions school is to match like with like: an East-group person pairs naturally with an East-group house, one whose sitting trigram is Kan, Zhen, Xun or Li. This page states the convention and computes your side of it; it does not predict outcomes, and it does not replace your own judgment.

Kua Number Calculator

Birth year (lichun boundary) and gender → kua number → trigram and East/West group → all eight directions and their wandering-year stars. Every formula step is shown, and the table’s symmetry and group structure can be checked cell by cell — and nothing is boiled into a percentage.

How the kua number is computed

Two pairs of century formulas — the mainstream convention, cross-checked here example by example against published kua tables. The remainder is the kua number; a remainder of 0 counts as 9, and a remainder of 5 parks on Kun (male) or Gen (female).

Birth years	Male	Female
1900–1999	(100 − last two digits) mod 9	(last two digits − 4) mod 9
2000–2099	(99 − last two digits) mod 9	(last two digits + 6) mod 9

Unified check: male (2 − year) mod 9, female (year − 5) mod 9. Both century pairs are congruent to the unified form mod 9 — this site asserts the equivalence for every year from 1900 to 2099 and both genders in its test suite, not just in prose.

Worked examples

Male, 1985 (the Yi Chou 乙丑 year): (100 − 85) = 15 → 15 mod 9 = 6 → Qian, kua 6, West group, Metal.
Female, 1990 (the Geng Wu 庚午 year): (90 − 4) = 86 → 86 mod 9 = 5 → remainder 5 parks on Gen, kua 8, West group, Earth.
Male, 2000 (the Geng Chen 庚辰 year): (99 − 0) = 99 → 99 mod 9 = 0 → a zero remainder counts as 9 → Li, kua 9, East group, Fire.
Lichun boundary: lichun 2026 falls at 2026-02-04 04:02 Beijing time. A male born 2026-02-03 counts as 2025 (Yi Si 乙巳) → Kun 2; born 2026-02-05 counts as 2026 (Bing Wu 丙午) → Kan 1. Same week, different life gua.

The full wandering-year table (8 life guas × 8 directions)

The Da You Nian verse, fully expanded. Each life gua holds Fu Wei in its own palace; the seven other directions take the seven stars in a fixed order. The table below is generated cell by cell from this site’s engine, and the test suite asserts two structural properties:

The table is fully symmetric — Kan and Li give each other Yan Nian, Qian and Dui give each other Sheng Qi, Qian and Kun give each other Yan Nian… every cell mirrors its transpose, and the twelve favorable pairings agree in both directions.
Groups never mix — the four favorable stars (Sheng Qi, Yan Nian, Tian Yi, Fu Wei) only ever land on same-group directions, the four unfavorable ones only on opposite-group directions. That is not a coincidence; it is how the model encodes the pre-heaven trigram line changes.

Life gua ＼ direction	坎 Kan North	艮 Gen Northeast	震 Zhen East	巽 Xun Southeast	离 Li South	坤 Kun Southwest	兑 Dui West	乾 Qian Northwest
乾 Qian West group	六煞	天医	五鬼	祸害	绝命	延年	生气	伏位
坎 Kan East group	伏位	五鬼	天医	生气	延年	绝命	祸害	六煞
艮 Gen West group	五鬼	伏位	六煞	绝命	祸害	生气	延年	天医
震 Zhen East group	天医	六煞	伏位	延年	生气	祸害	绝命	五鬼
巽 Xun East group	生气	绝命	延年	伏位	天医	五鬼	六煞	祸害
离 Li East group	延年	祸害	生气	天医	伏位	六煞	五鬼	绝命
坤 Kun West group	绝命	生气	祸害	五鬼	六煞	伏位	天医	延年
兑 Dui West group	祸害	延年	绝命	六煞	五鬼	天医	伏位	生气

The eight stars, their nine-star bodies and elements

Wandering star	Nine star	Element	Classical grade
生气 Sheng Qi — Growing Qi	贪狼 Tan Lang	木 Wood	most auspicious
延年 Yan Nian — Longevity	武曲 Wu Qu	金 Metal	most auspicious
天医 Tian Yi — Heavenly Doctor	巨门 Ju Men	土 Earth	auspicious
伏位 Fu Wei — Self Seat	辅弼 Fu Bi	木 Wood	mildly auspicious
祸害 Huo Hai — Mishap	禄存 Lu Cun	土 Earth	mildly unfavorable
六煞 Liu Sha — Six Killings	文曲 Wen Qu	水 Water	unfavorable
五鬼 Wu Gui — Five Ghosts	廉贞 Lian Zhen	火 Fire	most unfavorable
绝命 Jue Ming — Life Severed	破军 Po Jun	金 Metal	most unfavorable

The classical grades (most auspicious to most unfavorable) are how traditional texts rank the stars; wording varies slightly between texts, and this page uses the common grading, with its source noted on the methodology page.

School differences, stated openly

Year boundary: lichun (this page), lunar new year, and January 1 are all in circulation. People born near the boundary get different kua numbers under different conventions — that is disagreement about convention, not about arithmetic. This page computes with lichun and shows the exact instant it compared against.
Remainder 5: male parks on Kun 2, female on Gen 8 — the mainstream handling. A few texts park a male 5 on Gen 8 instead. This page follows the mainstream and marks the parking step in the result panel.
School membership: the life gua belongs to the Eight Mansions school. Other compass schools, such as Xuan Kong, do not use life guas at all; matching East-group people to East-group houses is a convention inside Eight Mansions, not a cross-school consensus.
Enumerated, never scored: this page gives your kua number, trigram, group and the eight direction stars — no composite fit percentage. The classical texts assign no weights, so every percentage online was invented by the site printing it.

Frequently asked questions

What is a kua number?: In Eight Mansions feng shui every person gets one life gua from birth year and gender: a number from 1 to 9 — 5 never appears as itself — a trigram, and a group. Kan 1, Zhen 3, Xun 4 and Li 9 form the East group; Kun 2, Qian 6, Dui 7 and Gen 8 form the West group. The group decides which four of the eight directions carry the favorable stars for that person.
Which year boundary does this page use?: The lichun instant, the same boundary this site uses for the year pillar: born before lichun, you count as the previous year. Many kua tables use January 1 or lunar new year instead. Those are different conventions, not errors, and they disagree for births near the boundary — this page computes with lichun and shows the exact instant it compared against.
My remainder is 5 — where is my gua?: Palace 5 belongs to the center and has no trigram, so a remainder of 5 is parked: a male counts as Kun 2, a female as Gen 8. This is the mainstream handling and the result panel marks it explicitly whenever it applies.
Where do the eight direction stars come from?: From the Da You Nian verse, a fixed table every Eight Mansions school shares: from your life gua the seven other directions receive Sheng Qi, Yan Nian, Tian Yi, Huo Hai, Liu Sha, Wu Gui and Jue Ming in a fixed order, and your own palace holds Fu Wei. The full 8 by 8 table is printed below. It is fully symmetric, and the four favorable stars always land on same-group directions — two structural facts you can check row by row.
What do I do with my East or West group?: The classical convention of the Eight Mansions school is to match like with like: an East-group person pairs naturally with an East-group house, one whose sitting trigram is Kan, Zhen, Xun or Li. This page states the convention and computes your side of it; it does not predict outcomes, and it does not replace your own judgment.