Eight Mansions (Kua) Calculator

How to use it

1. Enter your birth year, or your full date if you want the Chinese New Year boundary handled automatically.
2. Select your gender — the classical formula differs for men and women.
3. Read your four auspicious directions: Sheng Qi, Tian Yi, Wan Nian and Pei Wei.

How the kua number is calculated

The calculation is short enough to do by hand, which is useful because you will want to check the calculator rather than trust it blindly.

1. Take the last two digits of your Chinese birth year and add them together, then reduce to a single digit. So 1985 gives 8 + 5 = 13, then 1 + 3 = 4.
2. Apply the gender rule. For a man born before 2000, subtract that digit from ten. For a man born in 2000 or later, subtract it from nine. For a woman born before 2000, add five. For a woman born 2000 or later, add six. Reduce the result to a single digit again.
3. Handle the five. The number five is the centre palace and carries no direction, so it is reassigned — to two for men and to eight for women.

That third step is where most online calculators go wrong, along with the Chinese New Year boundary. If you were born in January or early February, you may belong to the previous Chinese year. The calculator handles both automatically when you enter a full date.

East group and West group

Your kua number places you in one of two groups, and this is the single most useful fact the system produces. East group is one, three, four and nine. West group is two, six, seven and eight.

The groups are exact opposites. Every direction that is lucky for the East group is unlucky for the West group, and vice versa. This means that once you know which group you are in, half of the directional options are already eliminated — and if you live with a partner from the other group, you have a genuine conflict to manage rather than a mistake to correct.

Interestingly, the group and the kua number are not the same thing, which trips people up. A four belongs to the East group but its own element is wood, not one of the two group-defining elements. The group tells you which direction set works for you; the number tells you the trigram you are aligned with.

Your four auspicious directions

Of the four good directions, two matter most and you should start there.

• Sheng Qi is your success and wealth direction. It is the strongest of the four. Face it from your front door and from your desk.
• Tian Yi is your health direction. It is the one to point your bed toward and the one that supports recovery and longevity.
• Wan Nian is lasting fortune — a slower, steadier direction associated with long-term projects.
• Pei Wei is personal growth, the direction that supports your individual development.

In practice, practitioners work with Sheng Qi and Tian Yi first, because those two carry most of the benefit and they are usually easy to apply to a front door and a bed. Chasing all eight at once produces a house that is technically correct and practically unliveable.

Living with a mismatched household

Couples and families frequently have different kua numbers, and the four directions can genuinely conflict. There are three workable approaches, in order of preference.

1. Split the function. Put each person's bed in their own best direction and let shared rooms use the East group positions, which most people tolerate well.
2. Prioritise the breadwinner. If only one direction can be optimised, use the Sheng Qi of whoever the household depends on financially.
3. Use the neutral centre. The centre of the home is friendly to both groups. Good lighting, an uncluttered middle and a well-placed water feature there will help whoever feels least served by the directional choices.

Do not try to make one direction good for two incompatible kua numbers by adding a charm. The traditional answer is functional compromise, not decoration.