Kua Number Calculator
Your kua number (命卦, mìngguà) sorts you into one of eight trigrams and hands you four directions that support you and four that work against you. It needs two things: your birth date and your gender. The date matters more than most calculators admit, because the solar year starts at Li Chun in early February, not on 1 January.
Enter your birth details
All eight numbers at a glance
Four numbers form the east group and four the west group. The directions below are the ones the tradition assigns to each number, listed strongest first.
| Kua | Gua | Group | Supporting directions | Directions to avoid |
|---|
How the calculation works
Two steps, one digit
Take the last two digits of the birth year and add them. If that gives two digits, add those too, until one digit is left. Born in 1987 gives 8 + 7 = 15, then 1 + 5 = 6. That digit goes into the formula for your gender and century.
The year starts in February
The calculation uses the solar year, which begins at Li Chun (立春, start of spring) on 3, 4 or 5 February. Born before that date, you use the year before. Born on 30 January 1990, you calculate with 1989. This is the step most calculators skip, and it moves the answer.
When the answer is 5
The number 5 sits in the centre of the Luoshu square and points nowhere, so the system reassigns it: men take 2 (Kun), women take 8 (Gen). It comes up often enough that it is worth knowing before you decide the calculator is broken.
One number is one room of the map
The home audit walks the nine areas of a house in the order that matters, with the two or three changes that make the most difference in each.
Frequently asked questions
Why does this calculator ask for my full birth date?
Because the kua number is calculated from the solar year, and the solar year begins at Li Chun, which falls on 3, 4 or 5 February. Anyone born between 1 January and that date has to calculate with the previous year. A calculator that only takes the year will get those people wrong, and the two answers can be eight directions apart.
My result is 5. What happened?
Nothing broke. The number 5 belongs to the centre of the Luoshu square and has no direction of its own, so the system reassigns it. Men use 2 (Kun) and women use 8 (Gen), and you then read the west group table for your new number. This tool does the reassignment for you and shows the original 5 so you can see where it went.
Is the kua number the same as my Chinese zodiac sign?
No. The zodiac sorts people into twelve animals by birth year. Kua numbers sort people into eight trigrams by birth year and gender, so two people born in the same year can land on different numbers, and one number covers millions of people born across many years. The two systems can also disagree about which direction suits you. They are separate tools that happen to share a calendar.
How accurate is the Li Chun date used here?
The tool uses the standard solar term approximation, which gives the correct day for every year from 1900 to 2099 apart from a handful of documented exceptions that are already handled. Li Chun also has a precise time, not just a date, so a birth on the Li Chun day itself is genuinely ambiguous at day-level precision. If that is you, the tool says so, and the honest answer is to check the exact hour against a full ephemeris or a practitioner.
This is a traditional framework, not a prediction. Kua numbers come from Eight Mansions feng shui, a compass system with its own internal logic, and nothing here is a claim about measurable outcomes. Treat the directions as a way to make choices you would otherwise make at random.