The short answer
Kua number compatibility is usually read in two steps. First, check whether you are in the same group, East or West. Then check the five-element relationship between your two numbers. Same-group couples and supportive element pairs are generally seen as harmonious. Different-group couples and element pairs that control each other are often described as needing more balance. These are traditional readings, not scientific ones.
Step 1: Find both kua numbers
Work out each partner’s kua number using their own birth year and gender. The kua number guide has the formula and a lookup table. Check the early-February date for either partner who was born in January or early February.
Step 2: Same group or different groups
- Same group. Both partners are East (kua 1, 3, 4 and 9) or both are West (kua 2, 6, 7 and 8). Their favourable directions are the same four, so it is easier to share spaces.
- Different groups. One partner is East and the other is West. The two groups’ favourable directions do not overlap at all, so shared spaces need more planning.
Step 3: The five-element cycle
Each kua number has an element: water for kua 1, wood for kua 3 and 4, fire for kua 9, earth for kua 2 and 8, and metal for kua 6 and 7.
| Pair | Relationship | Traditional reading |
|---|---|---|
| Same element (for example 3 and 4, or 2 and 8) | Same element | Generally harmonious |
| 1 and 3 or 4 | Water feeds wood | Supportive |
| 3 or 4 and 9 | Wood feeds fire | Supportive |
| 9 and 2 or 8 | Fire feeds earth | Supportive |
| 2 or 8 and 6 or 7 | Earth feeds metal | Supportive |
| 6 or 7 and 1 | Metal feeds water | Supportive |
| 1 and 9 | Water controls fire | More demanding |
| 9 and 6 or 7 | Fire controls metal | More demanding |
| 6 or 7 and 3 or 4 | Metal controls wood | More demanding |
| 3 or 4 and 2 or 8 | Wood controls earth | More demanding |
| 2 or 8 and 1 | Earth controls water | More demanding |
The “more demanding” pairs are not a verdict on a relationship. Traditional guidance is that they call for more care in arranging shared space, and many practitioners say the result depends on balance.
Step 4: Share the home
- Bedroom. Where the layout allows, use both partners’ Yan Nian (relationship) sectors for the bedroom. That is a common suggestion for couples in different groups. The bagua’s love and relationship corner is a separate, home-based idea that some couples use as well.
- Shared rooms. Orient the main living areas toward the sectors of the partner who is the main earner or who uses them most, as many practitioners suggest.
- Personal spaces. Each partner can use their own favourable sectors for a desk or a reading chair. The office desk guide explains how.
- The entrance. A front door in a favourable sector for one partner may suit the other too. The front door guide shows how to read it.
A note on the traditional reading
Practitioners do not all apply compatibility in the same way, and online calculators sometimes disagree. Birth dates close to Li Chun are the most common source of difference, so check those first. Treat the groups and the element pairs as a conversation starter, not as a verdict on a relationship.
For more on each number, see the Kua 1 guide, the Kua 2 and 8 guide, the Kua 3 and 4 guide, the Kua 6 and 7 guide and the Kua 9 guide. The Eight Mansions overview explains the system as a whole.
These are traditional guidelines, not scientific findings.