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The Ten Heavenly Stems: Jia, Yi, Bing, Ding, Wu, Ji, Geng, Xin, Ren and Gui

By Data Saju · Published October 3, 2026

The heavenly stems (天干) divide the energy of heaven into ten characters: each of the five elements in a yang and a yin form. The stem of your birth day is called your Day Master. In saju it stands for you, so every reading starts from it.

The ten stems at a glance

How to find your Day Master

Your Day Master is the first character of your day pillar — the stem-and-branch pair for the day you were born. If your day pillar is 辛巳, your Day Master is 辛 (Xin Metal). Day pillars run in a 60-day cycle, so you cannot read them off an ordinary calendar; you need an almanac. If you were born between 11 pm and 1 am, schools differ on which day you belong to, and the Day Master can change. Find yours here.

The ten Day Masters in more detail

甲 Jia Wood: the tall, straight tree

Once Jia sets a direction, it pushes straight ahead. Jia people take the lead naturally and have clear principles and pride. They are strong at starting new things and leading people, but they tend to stand firm until they snap rather than bend. When they learn to change direction, they grow for a long time, like a great tree.

Thrives in: launching new projects, education and planning — work that grows people and things. Watch for: the stubbornness of carrying everything alone.

乙 Yi Wood: the grass that bends but does not break

Soft but tenacious. Yi people adapt brilliantly to places and people and find their way through relationships. With good practical sense and warmth, they settle in anywhere. Practising saying what they want helps them avoid losing their share while accommodating others.

Thrives in: collaborative work, design, planning and service. Watch for: putting off decisions while reading the room.

丙 Bing Fire: the sun that lights the world

Bright and candid, Bing lights up everyone around it. Bing people dislike hiding things and express themselves freely, so they stand out anywhere. Their energy is big, so it can flare up and cool down quickly; with consistency, their light lasts.

Thrives in: work in front of people — broadcasting, sales, speaking. Watch for: big starts and weak finishes.

丁 Ding Fire: the candle in the dark

Delicate, warm focus. Quiet on the outside with a hot passion inside, Ding people look after each person carefully and shine by going deep in one field. They think a lot and can burn themselves up inside, so they need somewhere to share what they feel.

Thrives in: specialist skills, research, counselling and teaching — work that needs depth. Watch for: holding things in until they burst.

戊 Wu Earth: the dependable mountain

Trustworthy and embracing. Hard to shake, Wu people become the centre others lean on, and they can hold and coordinate many people. They can be slow to change and catch chances late, so moving first now and then helps.

Thrives in: management, mediation, property — work that holds the centre. Watch for: becoming still water that never moves.

己 Ji Earth: the field that grows seeds

Good practical sense and a talent for growing people and projects. Ji people look after substance and manage carefully, and find meaning in caring for and raising others. When worries pile up, it helps to mark the boundaries of their own field instead of trying to hold everything.

Thrives in: education and mentoring, finance and administration, care. Watch for: taking on other people's work until exhausted.

庚 Geng Metal: solid rock and raw ore

Strong decisiveness and loyalty. Right and wrong are clear to Geng, and what it takes on, it finishes. It has the power to decide boldly in a crisis. Its directness can be misunderstood; polishing words once turns charisma into trust.

Thrives in: roles that need decisions — technology, law, sport, leading in the field. Watch for: words and actions that turn sharp.

辛 Xin Metal: the finely cut jewel

Sharp senses and high standards for quality. Xin people have a refined eye for what is good, strong pride and a sense of dignity. They are strict with themselves and tire easily, so they need regular reminders that they are already enough.

Thrives in: design, quality, finance and professional work — anything that needs precision. Watch for: perfectionism that drives them too hard.

壬 Ren Water: the wide, deep river

Broad-minded and wise, with a free nature that flows anywhere. Ren people see the big picture and read the current well. Their energy overflows, so staying in one place is hard; with a goal to channel them, they flow far.

Thrives in: planning, strategy, logistics and trade — work that connects widely. Watch for: starting many things and scattering.

癸 Gui Water: rain and dew on the earth

Strong intuition and rich sensitivity. Gui people quietly seep in and bring life to their surroundings, and notice what others miss. They are easily affected by the mood around them, so they do well keeping people and places that fill them up close by.

Thrives in: research, analysis, counselling and the arts — work that uses intuition. Watch for: growing worries and anxiety alone.

Jia WoodYi WoodBing FireDing FireWu EarthJi EarthGeng MetalXin MetalRen WaterGui Water

The same Day Master changes with the season

Even with the same Day Master, the season of your birth month changes how it looks. A Jia tree born in spring is full of strength; in summer it needs water; in autumn it is being pruned; in winter it needs sunshine. That is why saju looks separately at the energy that balances heat and cold — called climate balance (調候). See the useful element and chart strength.

Relations between stems: combinations and clashes

Combining stems sit five places apart. When two people's Day Masters combine, it is read as a mutual attraction; when your luck brings a stem that combines with your Day Master, you tend to become bound to something — a contract, a promise, a relationship. Wu and Ji are the centre (Earth), so they have no clash partner.

A quick compatibility check between Day Masters

• Combining Day Masters are drawn to each other and bind easily — for example Jia and Ji, Bing and Xin.
• Generating Day Masters, where one element produces the other, help each other naturally — for example Ren (Water) nourishing Jia (Wood).
• Clashing Day Masters bump heads over methods, but can also supply what the other lacks.

Day Master compatibility is only a starting point. Real compatibility also looks at the day branch (the spouse palace), the elements each needs and the flow of luck. See how compatibility is read.

FAQ

Which shows me better, my Day Master or my zodiac sign? Your Day Master. The zodiac sign (year branch) is one of eight characters and is read as childhood and the first impression you give.

Do yang and yin stems have anything to do with gender? No. Yang stems are outward and direct; yin stems gather inward and are subtle. That is all.

Is a weak Day Master bad? No. A weaker chart shines when it has good people and surroundings to support it. Saju looks at balance, not strength alone.

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