The heavenly stems and earthly branches are two sets of traditional Chinese symbols, 10 stems and 12 branches, used for thousands of years to record time. Paired together, they form a 60-step cycle that underlies the traditional Chinese calendar and BaZi, the Four Pillars system.
This guide treats the system as cultural tradition and history first. Later sections show how astrology uses it for reflection and entertainment. We cover what the symbols are, why there are 60 pairings and not 120, how to find the stem and branch of a year, and how they connect to the zodiac and the Five Elements.
Heavenly Stems and Earthly Branches in Brief: Key Terms
The vocabulary has several overlapping names. Pronunciations below are rough guides for English speakers, not exact Mandarin.
| Term | Plain-English meaning | Rough sound |
|---|---|---|
| Tiangan (天干) | The 10 Heavenly Stems | tyen-gahn |
| Dizhi (地支) | The 12 Earthly Branches | dee-juh |
| Gan-Zhi (干支) | Stem-Branch, the combined system, also written Tiangan Dizhi | gahn-juh |
| Sexagenary | The base-60 cycle formed by pairing stems and branches | (English word) |
| Jia-Zi (甲子) | The first pairing, which opens the 60-step cycle | jyah-dzuh |
| BaZi (八字) | Eight Characters, the Four Pillars chart built from four stem-branch pairs | bah-dzuh |
So Tiangan Dizhi, Gan-Zhi, and stems and branches all point to the same system. For deeper BaZi vocabulary, see the BaZi glossary of stems, branches and Ten Gods.
The 10 Heavenly Stems (Tiangan)
The ten stems always come in this order: Jia, Yi, Bing, Ding, Wu, Ji, Geng, Xin, Ren, Gui. In the Five Elements framework, each carries a Yin or Yang polarity and an element, with two stems per element.
| Stem | Character | Rough sound | Polarity | Element |
|---|---|---|---|---|
| Jia | 甲 | jyah | Yang | Wood |
| Yi | 乙 | ee | Yin | Wood |
| Bing | 丙 | bing | Yang | Fire |
| Ding | 丁 | ding | Yin | Fire |
| Wu | 戊 | woo | Yang | Earth |
| Ji | 己 | jee | Yin | Earth |
| Geng | 庚 | gung | Yang | Metal |
| Xin | 辛 | shin | Yin | Metal |
| Ren | 壬 | ren | Yang | Water |
| Gui | 癸 | gway | Yin | Water |
Yin and Yang stems
The odd-numbered stems (Jia, Bing, Wu, Geng, Ren) are Yang, and the even-numbered ones (Yi, Ding, Ji, Xin, Gui) are Yin. That alternation matters when we pair them with branches.
A historical note: the stems once named the days of a 10-day week, but they are no longer used that way. Today they appear mostly alongside the branches in the sexagenary cycle. The word Heavenly is a traditional label, not a claim that the stems physically influence anything.
The 12 Earthly Branches (Dizhi)
The branches run in this order: Zi, Chou, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu, Hai. Each maps to one fixed animal of the Chinese zodiac.
| Branch | Character | Rough sound | Polarity | Animal |
|---|---|---|---|---|
| Zi | 子 | dzuh | Yang | Rat |
| Chou | 丑 | choh | Yin | Ox |
| Yin | 寅 | yin | Yang | Tiger |
| Mao | 卯 | mow | Yin | Rabbit |
| Chen | 辰 | chun | Yang | Dragon |
| Si | 巳 | suh | Yin | Snake |
| Wu | 午 | woo | Yang | Horse |
| Wei | 未 | way | Yin | Goat or Sheep |
| Shen | 申 | shun | Yang | Monkey |
| You | 酉 | yo | Yin | Rooster |
| Xu | 戌 | shu | Yang | Dog |
| Hai | 亥 | hi | Yin | Pig |
The branches alternate just like the stems. Zi, Yin, Chen, Wu, Shen and Xu are Yang. Chou, Mao, Si, Wei, You and Hai are Yin.
Two beginner traps
The branch Yin (the tiger, 寅) is a different word and character from the Yin of Yin-Yang. Likewise, the stem Wu (戊) and the branch Wu (午) are different characters that share a pinyin spelling. Whenever a chart says Wu, check which kind it is.
How Stems and Branches Combine into the 60-Year Cycle
Start with the first stem and first branch: Jia-Zi. Move both forward one step: Yi-Chou, then Bing-Yin, Ding-Mao and so on. The stems run out after ten, so Jia returns at step 11 and meets the 11th branch, Xu (Jia-Xu). The branches run out after twelve, so Zi returns at step 13 with Bing (Bing-Zi). The cycle ends at Gui-Hai, number 60, and then starts again at Jia-Zi.
It takes 60 steps because 60 is the smallest number divisible by both 10 and 12. Only at step 60 do both lists finish together.
Why 60 and not 120
You might expect 10 times 12, which is 120 pairings. The rule that cuts it in half is that Yang stems pair only with Yang branches, and Yin stems only with Yin branches. Because both lists alternate Yang, Yin, Yang, Yin, odd positions always meet odd positions and even meet even. Half of the 120 imaginable combinations never occur, leaving 60.
Table of all 60 pairings
| Steps | Pairings |
|---|---|
| 1-10 | 1 Jia-Zi 甲子, 2 Yi-Chou 乙丑, 3 Bing-Yin 丙寅, 4 Ding-Mao 丁卯, 5 Wu-Chen 戊辰, 6 Ji-Si 己巳, 7 Geng-Wu 庚午, 8 Xin-Wei 辛未, 9 Ren-Shen 壬申, 10 Gui-You 癸酉 |
| 11-20 | 11 Jia-Xu 甲戌, 12 Yi-Hai 乙亥, 13 Bing-Zi 丙子, 14 Ding-Chou 丁丑, 15 Wu-Yin 戊寅, 16 Ji-Mao 己卯, 17 Geng-Chen 庚辰, 18 Xin-Si 辛巳, 19 Ren-Wu 壬午, 20 Gui-Wei 癸未 |
| 21-30 | 21 Jia-Shen 甲申, 22 Yi-You 乙酉, 23 Bing-Xu 丙戌, 24 Ding-Hai 丁亥, 25 Wu-Zi 戊子, 26 Ji-Chou 己丑, 27 Geng-Yin 庚寅, 28 Xin-Mao 辛卯, 29 Ren-Chen 壬辰, 30 Gui-Si 癸巳 |
| 31-40 | 31 Jia-Wu 甲午, 32 Yi-Wei 乙未, 33 Bing-Shen 丙申, 34 Ding-You 丁酉, 35 Wu-Xu 戊戌, 36 Ji-Hai 己亥, 37 Geng-Zi 庚子, 38 Xin-Chou 辛丑, 39 Ren-Yin 壬寅, 40 Gui-Mao 癸卯 |
| 41-50 | 41 Jia-Chen 甲辰, 42 Yi-Si 乙巳, 43 Bing-Wu 丙午, 44 Ding-Wei 丁未, 45 Wu-Shen 戊申, 46 Ji-You 己酉, 47 Geng-Xu 庚戌, 48 Xin-Hai 辛亥, 49 Ren-Zi 壬子, 50 Gui-Chou 癸丑 |
| 51-60 | 51 Jia-Yin 甲寅, 52 Yi-Mao 乙卯, 53 Bing-Chen 丙辰, 54 Ding-Si 丁巳, 55 Wu-Wu 戊午, 56 Ji-Wei 己未, 57 Geng-Shen 庚申, 58 Xin-You 辛酉, 59 Ren-Xu 壬戌, 60 Gui-Hai 癸亥 |
How to Find the Stem and Branch of Any Year
To find your stem-branch year, you need only simple arithmetic. For the stem, look at the last digit of the year. For the branch, divide the year by 12 and look at the remainder.
| Last digit | Stem |
|---|---|
| 4 | Jia |
| 5 | Yi |
| 6 | Bing |
| 7 | Ding |
| 8 | Wu |
| 9 | Ji |
| 0 | Geng |
| 1 | Xin |
| 2 | Ren |
| 3 | Gui |
| Remainder after dividing by 12 | Branch |
|---|---|
| 4 | Zi (Rat) |
| 5 | Chou (Ox) |
| 6 | Yin (Tiger) |
| 7 | Mao (Rabbit) |
| 8 | Chen (Dragon) |
| 9 | Si (Snake) |
| 10 | Wu (Horse) |
| 11 | Wei (Goat) |
| 0 | Shen (Monkey) |
| 1 | You (Rooster) |
| 2 | Xu (Dog) |
| 3 | Hai (Pig) |
Worked examples: 2016 ends in 6, so the stem is Bing. Divided by 12, 2016 leaves a remainder of 0, so the branch is Shen. That makes 2016 Bing-Shen, the 3rd stem with the 9th branch. For 2017, the last digit 7 gives Ding and the remainder 1 gives You, so Ding-You. The same method gives Jia-Chen for 2024.
Chinese New Year vs. Lichun for January and February birthdays
There is a catch. In the everyday calendar view, the stem-branch year changes at Chinese New Year, which falls between late January and mid February. BaZi charts are often drawn with the year changing at Lichun, the Start of Spring, which usually falls around February 3 to 5. If you were born in January or February, the two conventions can give different years, so check which one your chart or calculator uses. The Hong Kong Observatory explains the stems and branches at https://www.hko.gov.hk/en/gts/time/stemsandbranches.htm.
Month, day and hour
The year is the easy pillar. The month, day and hour pillars depend on solar terms and the exact date and time, so they need an almanac or a calculator. If you are unsure of your birth hour, start with how to find your birth time. Check that any online calculator states which year boundary and time zone rules it uses.
Where They Came From: Legend, Evidence and Scholarly Views
It helps to keep three things apart: legend, documented evidence, and interpretation.
Legend of the Yellow Emperor and Da Rao
One popular story credits Da Rao with creating the system for the Yellow Emperor (Huangdi), with the date often given as around 2700 BC. This is legend, not archaeological evidence, and the date should not be treated as established history. It is best read as part of the cultural story.
Oracle bone evidence
The documented record points to the Shang dynasty. One cited oracle bone, dated by a general reference site to about 1000 BC, is described as carrying the full 60-term cycle. We have not checked this against a primary source, so treat the exact dating with care.
Debated original meanings
Some scholars discuss what the characters originally depicted. For example, Wikipedia notes that Jia has been linked to the idea of a turtle shell. There is no single settled account, and the earliest meanings are not fully certain.
Zodiac, Yin-Yang and the Five Elements
Each branch maps to one fixed animal, as the branch table shows. The twelve animals are simply the branch half of the year name. The stems are the other half, and carry the element and polarity. So 2016, Bing-Shen, is popularly called a Fire Monkey year: Bing is Yang Fire and Shen is the monkey.
Because there are 12 animals but 60 pairings, an animal returns every 12 years with a different stem. For a reflective look at the elements, see Five Elements and wellbeing.
Stem combinations
Traditional sources also describe the Five Compatibilities, in which certain stems are paired as combining partners. The example usually given is Jia with Ji. This is a traditional concept in Chinese metaphysics, not a prediction about people or relationships.
Calendar Use vs. Divination: Keep the Two Apart
The calendar use is the oldest and most straightforward: naming years and days so they can be recorded in a repeating sequence. That is historical record-keeping.
The metaphysical uses are separate. BaZi, feng shui, the I Ching and traditional Chinese medicine all draw on the stems and the Five Elements. These are cultural traditions without scientific validation, and nothing here is medical, financial or legal guidance.
How BaZi uses stems and branches
A BaZi chart has four pillars: year, month, day and hour. Each pillar is one stem-branch pair, giving eight characters, which is why BaZi means Eight Characters. Readers then reflect on the balance of Yin-Yang and the Five Elements across the chart. To learn more, read what BaZi and the Four Pillars are, or see the methodology page for how LuckTime describes its approach.
Historical and modern uses
The stems can also work like A, B, C, as ordinal labels for ranked or listed items. Some historical events are commonly named by their stem-branch year. The 1894 Jiawu War and the 1911 Xinhai Revolution are examples, and the year method above gives Jia-Wu for 1894 and Xin-Hai for 1911. We have not checked these names against a primary source here, so verify them before citing.
A Book for Going Deeper, and a Gentle Next Step
One option is Zhongxian Wu and Karin Taylor Wu's Heavenly Stems and Earthly Branches – TianGan DiZhi: The Heart of Chinese Wisdom Traditions. Its listing describes it as covering 22 symbols, their characteristics and interactions, and including Song-dynasty poetic summaries. You can see the listing at https://www.amazon.com/Heavenly-Stems-Earthly-Branches-Traditions/dp/1848192088. Books differ in school and style, so treat any single author as one perspective.
To recap: ten stems, twelve branches, sixty pairings, one repeating cycle. A personal BaZi chart places your birth year, month, day and hour into that form as a reflective cultural lens, not a forecast. If you would like to see your own pillars laid out in plain English, you are welcome to explore a Life Blueprint reading.
Frequently asked questions
What are the Heavenly Stems and Earthly Branches?
They are 10 stems and 12 branches, traditional Chinese symbols used to record years, months, days and hours. Paired together, they make a 60-step cycle.
What is Tiangan Dizhi (Gan-Zhi)?
Tiangan Dizhi is the Chinese name for the Heavenly Stems (Tiangan) and Earthly Branches (Dizhi). Gan-Zhi, or Stem-Branch, is the same system under its shorter name.
Why are there 60 combinations and not 120?
Yang stems pair only with Yang branches, and Yin stems only with Yin branches. That removes half of the 120 possible pairs and leaves 60.
How do I find the stem and branch of my birth year?
Use the last digit of the year for the stem and the remainder after dividing by 12 for the branch, using the lookup tables above. For January and February births, check whether your source changes the year at Chinese New Year or at Lichun.
Is there a calculator for the four pillars?
Online four-pillars calculators exist. The year is easy by hand, but the month, day and hour pillars need an almanac or calculator and an accurate birth time.
LuckTime readings and guides are for entertainment and self-reflection. They are not medical, financial, legal or psychological advice.