Heavenly Stems & Earthly Branches: Meaning & Chart

The 10 Heavenly Stems and 12 Earthly Branches

The 10 Heavenly Stems

The ten Heavenly Stems follow a fixed order and, in later Chinese cosmology, each carries a Yin or Yang quality and one of the Five Phases (五行, Wuxing).

Images such as “Jia is a large tree” and “Bing is the Sun” belong to later interpretive traditions, not proven Shang meanings. The earliest evidence presents the stems mainly as ordered calendrical signs.

That ordinal function survives in modern Chinese. Jiafang (甲方) and Yifang (乙方) mean Party A and Party B; Jia and Yi also distinguish grades, categories, disease types, and chemical terms such as methanol (甲醇) and ethanol (乙醇).

The 12 Earthly Branches

Later traditions connected the twelve Earthly Branches with zodiac animals, double hours, compass sectors, seasons, and other calendrical correspondences.

The Earthly Branches are not simply another name for the twelve zodiac animals. The branch sequence is older and also organizes hours, months, directions, seasons, and other calendrical relationships. The animals became its most recognizable popular layer.

English readers should also distinguish Wu (戊, Wù), the fifth Heavenly Stem, from Wu (午, Wǔ), the seventh Earthly Branch. 戊 is the Yang Earth stem; 午 is the Horse branch associated with midday.

The twelve animal signs follow the older sequence explained in Chinese Zodiac.

Heavenly Stems vs Earthly Branches

The final distinction belongs to later BaZi (八字) interpretation. “Stems are external and branches are internal” is not a historical definition of Gan-Zhi.

How the 60 Jiazi Cycle Works

Why Are There 60 Pairs Instead of 120?

Ten stems and twelve branches could produce 120 combinations if every sign were freely matched. Gan-Zhi instead advances both sequences one position at a time:

Jia-Zi → Yi-Chou → Bing-Yin → Ding-Mao → Wu-Chen → Ji-Si → Geng-Wu → Xin-Wei → Ren-Shen → Gui-You

After the tenth pair, the stems return to Jia while the branches continue. The two sequences return to their starting positions together after sixty steps because 60 is the least common multiple of 10 and 12.

Because the sequences move together, odd-numbered stems meet only odd-numbered branches, while even-numbered stems meet even-numbered branches. Later tradition describes this as Yang pairing with Yang and Yin with Yin. This does not independently remove sixty combinations; it interprets the parity already produced by the synchronized sequence.

The sixtieth pair is Gui-Hai (癸亥). The following step returns to Jia-Zi (甲子), completing the cycle.

How to Read a Stem-Branch Pair

Consider Geng-Zi (庚子), the 37th pair:

• Geng (庚) is the seventh Heavenly Stem and is later classified as Yang Metal.
• Zi (子) is the first Earthly Branch, associated with the Rat and Water.
• Geng-Zi may therefore be called a Metal Rat year in popular usage.
• At its foundation, however, Geng-Zi is position 37 in the repeating sequence.

The ordered pair came first; its elemental, zodiac, and interpretive meanings were added later.

Each stem carries a later classification explored in Yin and Yang and Five Elements.

The Complete 60 Jiazi Chart

A group of ten consecutive pairs is called a xun (旬). The full cycle contains six xun, each beginning with Jia.

A full sixty-term cycle is also associated with the expression huajia (花甲). Reaching age sixty means completing one return of the year cycle.

Historical Origins of Gan-Zhi

Late Shang Oracle-Bone Evidence

The earliest securely attested written evidence for the stem-branch cycle comes from late Shang oracle-bone inscriptions of the late second millennium BCE. Some surviving bones contain complete sexagenary tables, while many divination inscriptions begin by identifying the day with a Gan-Zhi pair.

A record might begin with a day label such as Gui-Wei (癸未), followed by the divination statement. The pair functions as a date marker, showing that the sequence was already established when these inscriptions were made.

Heavenly Stems also appear in the ancestral names of Shang rulers, including Da Jia (大甲), Wu Ding (武丁), and Di Xin (帝辛). Their precise relationship to lineage, ritual scheduling, and royal organization remains debated, but the evidence places the stems in both calendrical and royal ancestral contexts.

From a Day Count to a Wider Cultural System

The modern system therefore contains several historical layers: a Shang-era foundation of ordered day signs, later Yin-Yang and Five-Phase correspondences, and subsequent zodiac, BaZi, Na Yin, Tai Sui, and almanac applications.

Did the Yellow Emperor Invent Gan-Zhi?

Later traditional accounts attribute the creation of Jiazi to Da Nao (大挠), a figure associated with the Yellow Emperor (黄帝). This story gives Gan-Zhi a place within Chinese cultural memory, while oracle bones provide the earliest securely datable physical evidence.

The inscriptions show that the cycle was mature by the late Shang period, but they do not identify one inventor or reveal exactly when the system began.

How Gan-Zhi Records Years, Months, Days, and Hours

Although Gan-Zhi is now closely associated with year names, its earliest clearly documented function was recording days. Its application to years, months, and hours developed over different historical periods.

Traditional branch months run from Yin (寅) through Chou (丑), but calendrical and BaZi month boundaries often follow solar terms rather than the first day of a lunar month. Month stems derive from the year stem through the Five Tigers method (五虎遁), while hour stems follow the day stem through the Five Rats method (五鼠遁).

The year, month, day, and hour pairs form the Four Pillars (四柱). Their eight characters constitute BaZi (八字), a later specialized application of Gan-Zhi rather than its original purpose.

How to Read a Gan-Zhi Year

A known Jia-Zi year provides a simple reference point:

• 1984: Jia-Zi (甲子)
• 1985: Yi-Chou (乙丑)
• 1986: Bing-Yin (丙寅)
• 2020: Geng-Zi (庚子)
• 2044: Jia-Zi (甲子)

Both sequences advance by one position each year, and the same pair returns every sixty years. This is sufficient for following year names, but exact day and hour pillars require a reliable calendrical tool because local time, date boundaries, solar terms, and calculation conventions may affect the result.

Use the Chinese Zodiac Calculator to identify a birth year’s animal and Gan-Zhi pair.

Chinese New Year or Lichun?

Two boundary conventions appear in different contexts:

• Popular zodiac and Lunar New Year usage: The animal year usually changes on Chinese New Year, the first day of the first lunar month.
• Some BaZi and solar-term systems: The year pillar changes at Lichun (立春), the Start of Spring, usually around February 3–5.

People born between Lichun and Chinese New Year should check which convention a calendar, calculator, or practitioner follows.

Gan-Zhi is also not another name for the Chinese lunar calendar. The traditional Chinese calendar is a lunisolar system combining lunar months, solar terms, and leap-month rules; Gan-Zhi is a repeating system for naming and ordering units of time.

The broader calendar structure is explained in [Chinese Calendar] and 24 Solar Terms.

Gan-Zhi, the Chinese Zodiac, and Later Systems

Earthly Branches and the Chinese Zodiac

The Chinese zodiac assigns one animal to each Earthly Branch, but the branch sequence predates the standardized animal list. Early manuscripts preserve alternative pairings, while Eastern Han texts contain a sequence substantially matching the modern zodiac. Historically, the animals were attached to the branches rather than the branches being created from the animals.

The animals made the sequence easier to remember and use in age reckoning and popular culture, while the branches retained broader functions in timekeeping, directions, seasons, and calendrical systems.

The development of these pairings is explained in [Chinese Zodiac Origin].

Heavenly Stems, Yin-Yang, and the Five Phases

Later tradition assigns two stems to each Five Phase: Jia and Yi to Wood, Bing and Ding to Fire, Wu and Ji to Earth, Geng and Xin to Metal, and Ren and Gui to Water. The first stem in each pair is Yang and the second is Yin.

This framework became important in cosmology, medicine, divination, and BaZi, but it is a later interpretive layer rather than the proven original meaning of the Shang stem signs.

Later Systems Built on Gan-Zhi

These traditions use Gan-Zhi as an underlying language, but they do not represent its earliest purpose. A calendar date, zodiac sign, BaZi chart, and Tai Sui interpretation may use the same characters while asking different questions.

The symbolic elemental names are covered in Na Yin Five Elements, while annual branch relationships are discussed in [Tai Sui] and Ben Ming Nian.

How Gan-Zhi Shaped Chinese Culture

Gan-Zhi supplied a compact language for dates, periods, categories, historical events, and technical relationships across Chinese and East Asian cultures.

These uses fall into two broad categories: calendrical and documentary uses identify time and order, while astrological and divinatory uses interpret relationships among the signs. Both are historically important, but they are not the same function.

Gan-Zhi is one of the foundational time systems covered in Chinese Culture.

Common Myths and Misunderstandings

• Myth: Gan-Zhi is the same as the Chinese zodiac.
  The zodiac animals are attached only to the twelve Earthly Branches. Gan-Zhi also includes ten stems and broader calendrical functions.
• Myth: Stems and branches were created only to name years.
  Their earliest securely documented use was primarily for naming days in Shang oracle-bone inscriptions.
• Myth: Ten stems times twelve branches should produce 120 pairs.
  The two sequences advance together rather than combining freely, so they return to their shared starting point after sixty steps.
• Myth: Five-Phase and zodiac meanings existed fully formed in the Shang period.
  The earliest evidence supports ordered day signs. Elemental, animal, and cosmological correspondences developed later.
• Myth: The Yellow Emperor’s invention of Gan-Zhi is verified history.
  It is an influential traditional account. Late Shang oracle bones provide the earliest securely attested physical evidence.
• Myth: Gan-Zhi is another name for the lunar calendar.
  Gan-Zhi is a cyclical naming system; the Chinese calendar is lunisolar and includes lunar months, solar terms, and leap months.
• Myth: Every tradition changes the year on Chinese New Year.
  Popular zodiac usage generally follows Chinese New Year, while some BaZi systems use Lichun.
• Myth: “Heavenly” and “Earthly” reveal the signs’ original Shang meanings.
  These are later traditional names and translations; the signs’ earliest meanings remain debated.
• Myth: Wu (戊) and Wu (午) are the same sign.
  戊 is the fifth Heavenly Stem and is pronounced Wù; 午 is the seventh Earthly Branch and is pronounced Wǔ.
• Myth: BaZi explains the only real purpose of stems and branches.
  BaZi is one later application. Gan-Zhi first functioned as a system of order and time notation.

Final Thoughts

The Heavenly Stems and Earthly Branches are best understood as a layered system:

• Foundation: An ancient ordered sequence and 60-day cycle securely attested in late Shang writing.
• Cosmological layer: Yin-Yang, Five Phases, directions, seasons, and zodiac animals added or systematized later.
• Application layer: BaZi, Na Yin, Tai Sui, almanacs, date selection, and other technical traditions.

This explains how the same signs can appear in an oracle-bone date, the names Jia-Wu War and Xin-Hai Revolution, a modern contract’s Party A and Party B, and a BaZi chart without serving the same purpose in each context.

FAQs About Heavenly Stems and Earthly Branches

What are the Heavenly Stems and Earthly Branches?

They are two ordered Chinese sign systems: ten Heavenly Stems and twelve Earthly Branches. The sequences advance together to form sixty recurring pairs used to identify days, years, months, hours, and later cultural correspondences.

What are the 10 Heavenly Stems in order?

The sequence is Jia (甲), Yi (乙), Bing (丙), Ding (丁), Wu (戊), Ji (己), Geng (庚), Xin (辛), Ren (壬), and Gui (癸).

What are the 12 Earthly Branches in order?

The sequence is Zi (子), Chou (丑), Yin (寅), Mao (卯), Chen (辰), Si (巳), Wu (午), Wei (未), Shen (申), You (酉), Xu (戌), and Hai (亥).

What does Gan-Zhi mean?

Gan-Zhi (干支) is the shortened Chinese name for the combined Heavenly Stem and Earthly Branch system. The conventional English terms reflect later terminology and may not preserve the signs’ original Shang meanings.

Why are there 60 Jiazi pairs instead of 120?

The ten stems and twelve branches advance simultaneously rather than combining freely. Their sequences return to the first positions together after sixty steps, the least common multiple of ten and twelve.

What does Jiazi mean?

Jia-Zi (甲子) is the first pair in the cycle: Jia is the first Heavenly Stem and Zi is the first Earthly Branch. The term can also refer more broadly to the complete sixty-pair sequence.

Are the Earthly Branches the same as the Chinese zodiac?

No. Zodiac animals are later cultural correspondences attached to the branches. Earthly Branches also organize traditional hours, months, directions, seasons, and stem-branch dates.

How are the Heavenly Stems related to the Five Elements?

Later tradition assigns Jia and Yi to Wood, Bing and Ding to Fire, Wu and Ji to Earth, Geng and Xin to Metal, and Ren and Gui to Water. Each pair contains one Yang stem and one Yin stem.

Are Gan-Zhi signs used for days and hours as well as years?

Yes. Gan-Zhi records years, months, days, and double hours. Day dating is its earliest securely documented use, while four pairs for a birth time form the Four Pillars or Eight Characters.

What is the difference between Gan-Zhi and BaZi?

Gan-Zhi is the underlying system of stems, branches, and sixty recurring pairs. BaZi is a later divinatory system that analyzes the four pairs assigned to a person’s birth year, month, day, and hour.

Does a Gan-Zhi year begin at Chinese New Year or Lichun?

Popular zodiac and Lunar New Year usage generally changes at Chinese New Year. Some BaZi and solar-term traditions change the year pillar at Lichun. People born near these dates should confirm which convention is being used.