Hidden Stems and Their Weights: what is inside each earthly branch

Hidden stems and weights — ink-wash illustration

Every earthly branch holds hidden stems

A Bazi chart has four visible heavenly stems — one per pillar — but the four earthly branches below them each contain one to three more stems, hidden inside. These hidden stems (藏干, cáng gān) are part of the chart, and the calculator counts them when it tallies the five elements. For the underlying framework, see How to Read a Bazi Chart: A Step-by-Step Guide for Beginners.

If you look at only the four visible stems, you see four data points. The hidden stems add up to twelve more, bringing the total to as many as sixteen. Ignoring them would be like reading a sentence with half the words covered.

The full hidden-stem table

The table below lists what is inside each of the twelve earthly branches. The order within each branch matters: the first stem listed is the main qi (本气, běn qì), the second is the middle qi (中气, zhōng qì), and the third — when present — is the residual qi (余气, yú qì).

Branch Main qi (本气) Middle qi (中气) Residual qi (余气)
Zi 子 Gui 癸 (Water) — —
Chou 丑 Ji 己 (Earth) Gui 癸 (Water) Xin 辛 (Metal)
Yin 寅 Jia 甲 (Wood) Bing 丙 (Fire) Wu 戊 (Earth)
Mao 卯 Yi 乙 (Wood) — —
Chen 辰 Wu 戊 (Earth) Yi 乙 (Wood) Gui 癸 (Water)
Si 巳 Bing 丙 (Fire) Geng 庚 (Metal) Wu 戊 (Earth)
Wu 午 Ding 丁 (Fire) Ji 己 (Earth) —
Wei 未 Ji 己 (Earth) Ding 丁 (Fire) Yi 乙 (Wood)
Shen 申 Geng 庚 (Metal) Ren 壬 (Water) Wu 戊 (Earth)
You 酉 Xin 辛 (Metal) — —
Xu 戌 Wu 戊 (Earth) Xin 辛 (Metal) Ding 丁 (Fire)
Hai 亥 Ren 壬 (Water) Jia 甲 (Wood) —

Four branches (Zi, Mao, You, and Wu) are called "pure" branches because they contain only one or two stems of a single element family. The other eight branches are "mixed" — they hold stems from two or three different elements, reflecting the transitional nature of those positions in the cycle.

How the calculator weights each tier

Not all hidden stems count equally. The main qi gets full weight, the middle qi gets half, and the residual qi gets less than a third. The method is easier to compare with Bazi Without a Birth Hour: what three pillars can still tell you.

Tier Position in the branch Weight
Main qi (本气) First hidden stem 1.0
Middle qi (中气) Second hidden stem 0.5
Residual qi (余气) Third hidden stem 0.3

A visible heavenly stem — the one sitting on top of the branch — also gets a weight of 1.0. So a visible stem and a main qi hidden stem carry the same weight in the five-element tally.

Example: the Yin branch (寅)

Yin contains Jia Wood (main qi, weight 1.0), Bing Fire (middle qi, weight 0.5), and Wu Earth (residual qi, weight 0.3). If the day pillar is, say, Ren Water (壬), then these three hidden stems are labeled:

  • Jia Wood → Indirect Resource (weight 1.0)
  • Bing Fire → Indirect Wealth (weight 0.5)
  • Wu Earth → Seven Killings (weight 0.3)

The ten-god label is always relative to the Day Master, just as it is for visible stems. The difference is the weight: the Indirect Resource at 1.0 counts twice as much as the Indirect Wealth at 0.5 and more than three times as much as the Seven Killings at 0.3.

How the five-element tally is built

The calculator walks through all four pillars, adds the visible stems at weight 1.0, and then adds each hidden stem at its tier weight. The sum per element is the five-element count shown on the chart. This point connects directly with True Solar Time in Bazi: why your clock is not your birth time.

Take a chart with pillars 癸亥 / 癸亥 / 丙子 / 壬辰 (year Gui-Hai, month Gui-Hai, day Bing-Zi, hour Ren-Chen):

Source Stem Element Weight
Year stem Gui 癸 Water 1.0
Year branch Hai: main qi Ren 壬 Water 1.0
Year branch Hai: middle qi Jia 甲 Wood 0.5
Month stem Gui 癸 Water 1.0
Month branch Hai: main qi Ren 壬 Water 1.0
Month branch Hai: middle qi Jia 甲 Wood 0.5
Day stem Bing 丙 Fire 1.0
Day branch Zi: main qi Gui 癸 Water 1.0
Hour stem Ren 壬 Water 1.0
Hour branch Chen: main qi Wu 戊 Earth 1.0
Hour branch Chen: middle qi Yi 乙 Wood 0.5
Hour branch Chen: residual qi Gui 癸 Water 0.3

Totals: Water 6.3, Wood 1.5, Fire 1.0, Earth 1.0, Metal 0.0.

The Day Master is Bing Fire, and the chart has 6.3 parts Water against 1.0 part Fire. The hidden stems account for most of the Water total — without them, you would see only three visible Water stems (3.0), missing the other 3.3 that sit inside the branches.

Why the weights matter

The five-element count feeds into the calculator's assessment of whether the Day Master is strong or weak, and which elements the chart needs more or less of. A hidden stem at 0.3 contributes far less than one at 1.0, so a residual-qi stem is a minor presence, not a major one. Getting the weights wrong would distort the balance and potentially flip the strong/weak assessment.

The weights used by this calculator (1.0 / 0.5 / 0.3) are the standard proportions found in most modern Bazi references. Some classical sources use slightly different ratios, but the three-tier principle — main qi is strongest, middle qi is moderate, residual qi is weakest — is universal across schools.

Open your chart in the free Bazi calculator — it lists the hidden stems under each branch, labels each one with its ten-god name, and shows the weighted five-element totals.
Sifu Xion

Sifu Xion · 8th-generation Form School practitioner · M.Sc. Data Science, Shanghai.

Cast your own chart with the free Bazi calculator to see which configuration you carry. If you would rather have him read the whole chart himself, the full written reading covers all ten gods, your luck pillars and what to do with them.