Chinese Zodiac Compatibility: Trines, Harmonies, Clashes

Chinese zodiac compatibility is built on a simple idea: some animals sit naturally well together, some pair off as close allies and some stand directly opposite one another. Traditional Chinese astrology names three kinds of relationship between the twelve animals, the three-harmony trines, the six harmonies and the six clashes, and these are exactly the relationships our BaZi engine uses when it compares branches. This guide explains each one, gives a table for all twelve animals and then explains why your birth year animal is only one part of the picture.

As ever, treat it as reflection and tradition, not a verdict on any relationship.

How does Chinese zodiac compatibility work?

The twelve animals are the Earthly Branches, set out in a fixed order: Rat, Ox, Tiger, Rabbit, Dragon, Snake, Horse, Goat, Monkey, Rooster, Dog, Pig. The relationships between them follow the geometry of that circle:

• Trines (three harmonies): animals four places apart, forming groups of three.
• Harmonies (six harmonies): pairs that join across the circle, often called "secret friends".
• Clashes (six clashes): animals exactly opposite each other, six places apart.
• Neutral: everything else. Most animal pairs are neutral, which is fine; it simply means no special link.

Two people born under the same animal are a separate case: a "same" pairing, which means shared character and shared blind spots. Remember too that BaZi counts the year from Lichun in early February, not from Chinese New Year, so a January or early February birthday may belong to the previous animal. Our Year of the Goat guide explains the overlap.

What are the three-harmony trines?

The strongest "friendly" relationship is the trine. The twelve animals divide into four groups of three, and members of a group share a temperament and an element:

Animals in the same trine tend to understand each other's motives and often share goals, so friendship and partnership can feel easy. The caution is that you can reinforce each other's habits as well as your strengths. Tradition describes it as natural kinship rather than guaranteed harmony.

What are the six harmonies, or "secret friends"?

The six harmonies pair animals who complement each other, often because each supplies what the other needs. Nicknamed "secret friends", these pairs can feel unexpectedly close:

• Rat and Ox
• Tiger and Pig
• Rabbit and Dog
• Dragon and Rooster
• Snake and Monkey
• Horse and Goat

Notice that the two animals in a harmony pair come from different trines, so a secret friend is often someone quite unlike you who fills a gap, such as the Ox's patience for the Rat's quick ideas. Our Year of the Goat article mentions the Horse and Goat pair for exactly this reason: they are one of the classic harmonies, so a Goat year is traditionally gentle for Horses.

What are the six clashes?

A clash is the relationship between animals opposite each other on the circle:

• Rat and Horse
• Ox and Goat
• Tiger and Monkey
• Rabbit and Rooster
• Dragon and Dog
• Snake and Pig

Opposite animals look at life from the other side of the table. Tradition says clash pairs bring friction, differing rhythms and the feeling of being pulled in opposite directions. They can also be magnetic, because each sees what the other overlooks. In Western astrology the nearest comparison is opposite signs, which are drawn together and challenged in equal measure; see our guide to the most compatible zodiac signs for that side of the story.

A clash is not a curse, and it is not a reason to avoid a person. A Rat and a Horse in a happy marriage are entirely possible. It simply names where extra patience and communication are likely to be needed.

Which animals suit which? A table for all 12

Each row lists the animal's trine friends, its secret friend (harmony), and its clash. Every other animal is neutral.

Each animal has two trine friends, one secret friend, one clash and seven neutral animals, besides its own. If you were born in January or early February, check which animal you are in BaZi first, since the year boundary is Lichun.

Is the birth year animal the whole picture?

Not at all, and this is the most important point on the page. The year animal is only one of four pillars. A full BaZi chart also has a month, day and hour pillar, each with its own Heavenly Stem and Earthly Branch. The day pillar, and in particular the Day Master (the stem of the day), is considered the heart of the chart, and the month branch, which sets the season of birth, carries a lot of weight.

So when two charts are compared, the same trine, harmony and clash relationships are looked for between all four pillars, not only between the year animals. Two people whose year animals clash might have a harmony between their day branches. Two "perfect" year animals might share a clash elsewhere. Stems and the balance of the five elements (Wood, Fire, Earth, Metal, Water) matter too. If you would like to see how this works, our beginner's guide to BaZi and the Four Pillars is the place to start, and the Four Pillars report reads your Day Master and element balance in full.

How should I use the Chinese zodiac for relationships?

Use the table as a conversation starter. Look up your own animal and a partner's, friend's or colleague's, and see which link they share. If it is a trine or harmony, enjoy the sense of ease. If it is a clash, treat it as a prompt to listen more. If it is neutral, which most pairs are, nothing special is implied, and the rest of the chart has more to say. The Western equivalent of this starting point is the Sun sign, and its limits are the same: it is the first layer, never the last.