BaZi Basics: Four Pillars, Stems and Branches, Yin-Yang and the Five Elements

These are the words to know before any chart makes sense. A BaZi chart is four pillars, each with a stem above and a branch below, and the stem of the day pillar is you.

Index of this group

12 terms

BaZi 八字
BaZi, the “eight characters,” takes one Heavenly Stem and one Earthly Branch for each of the year, month, day and hour of birth, giving four pillars of eight characters that describe the five-element makeup of that moment. Read more →
Four Pillars 四柱
The Four Pillars are the four stem-branch pairs of a BaZi chart: year, month, day and hour. Each has a Heavenly Stem on top and an Earthly Branch below, and each stands for a palace and a stage of life. Read more →
Ten Heavenly Stems 十天干
The Ten Heavenly Stems, Jia through Gui, are ten symbols, each with a polarity and an element, that form the top character of every BaZi pillar. The classic Di Tian Sui gives each one a short verse. Read more →
Twelve Earthly Branches 十二地支
The Twelve Earthly Branches, Zi, Chou, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu and Hai, match the twelve months, the twelve double-hours and the twelve zodiac animals. Each is the lower half of a pillar and holds hidden stems. Read more →
Yin and yang 陰陽
Yin and yang split the stems and branches in two: Jia, Bing, Wu, Geng and Ren are yang stems; Yi, Ding, Ji, Xin and Gui are yin. Whether two stems share a polarity decides a Ten God’s direct or indirect form. Read more →
Five Elements 五行缺什麼
The Five Elements are Wood, Fire, Earth, Metal and Water, linked by a generating cycle (Wood feeds Fire, Fire makes Earth…) and a controlling cycle (Wood controls Earth, Earth controls Water…). BaZi reads a chart by their amounts and interplay. Read more →
Day Master 日主
The Day Master is the Heavenly Stem of the birth day in a BaZi chart, and it stands for the person themselves. Each of the ten stems, from Jia to Gui, forms one Day Master and sets the core tone of that person’s character. Read more →
Hidden Stems 地支藏干
Hidden Stems are the one to three Heavenly Stems held inside each Earthly Branch. They are not written on the face of a chart, yet they decide the real weight of the Ten Gods and of the five elements. Read more →
Sixty Jiazi 六十甲子
The Sixty Jiazi are the sixty stem-branch pairs made by matching the ten stems and twelve branches in order, from Jia-Zi to Gui-Hai. They count years, months, days and hours, and every BaZi pillar is one of them. Read more →
Nayin elements 納音五行
The Nayin elements (na yin, 納音) pair the sixty jiazi into thirty image-based elements, such as Gold in the Sea or Fire in the Furnace. The Nayin of the year pillar is called the year life. Read more →
Which element are you missing 五行缺什麼
Which element are you missing asks which of the five elements, Metal, Wood, Water, Fire or Earth, is absent or very weak in a BaZi chart. The thin element marks an energy to build up through colour, direction, work and daily habit. Read more →
The useful element 五行補洩剋
The useful element is the one a chart most needs strengthened. Finding it starts with the Day Master: a strong one wants draining or controlling, a weak one wants support, and colour, direction and daily habit follow from there. Read more →

Other groups

Chart Casting & CalendarHow the pillars are cast, solar terms, true solar time, the Zi hour, Conception Pillar Ten Gods & CombinationsFriend to Direct Resource, plus seven classic pairings Strength & Favorable ElementsStrong or weak, favorable elements, climate, twelve life stages Chart StructuresThe eight regular structures, Jian Lu, follow, transformation, dominant Stem & Branch RelationsCombine, meet, clash, punish, harm, break, arch; stem combinations Symbolic StarsNobleman, Academic Star, Peach Blossom, Traveling Horse, the Void… Luck Pillars & Annual LuckLuck pillars, annual and monthly pillars, Tai Sui, San Yuan Jiu Yun Life AreasWealth, family, study, marriage, career, partnerships

About this glossary

Every definition is taken from the one-line definition on the matching page of this site, so when a page is updated, the glossary follows; only terms without their own page are written here. Usage varies a little between schools; this site follows the Zi Ping BaZi usage common in Taiwan. Everything here is for reference and entertainment only.

Find these terms on your own chart

A free chart lists your Four Pillars, Ten Gods, hidden stems and Five Elements; the in-depth reading then turns them into twelve areas of life.

BaZi basics terms FAQ

What does “BaZi” mean in BaZi?

BaZi, the “eight characters,” takes one Heavenly Stem and one Earthly Branch for each of the year, month, day and hour of birth, giving four pillars of eight characters that describe the five-element makeup of that moment.

What does “Four Pillars” mean in BaZi?

The Four Pillars are the four stem-branch pairs of a BaZi chart: year, month, day and hour. Each has a Heavenly Stem on top and an Earthly Branch below, and each stands for a palace and a stage of life.

What does “Ten Heavenly Stems” mean in BaZi?

The Ten Heavenly Stems, Jia through Gui, are ten symbols, each with a polarity and an element, that form the top character of every BaZi pillar. The classic Di Tian Sui gives each one a short verse.

What does “Twelve Earthly Branches” mean in BaZi?

The Twelve Earthly Branches, Zi, Chou, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu and Hai, match the twelve months, the twelve double-hours and the twelve zodiac animals. Each is the lower half of a pillar and holds hidden stems.