10 Heavenly Stems and 12 Earthly Branches

Heavenly Stems & Earthly Branches originated from the observation of astronomical phenomena in ancient China. 10 Heavenly Stems are Jia (甲), Yi (乙), Bing (丙), Ding (丁), Wu (戊), Ji (己), Geng (庚), Xin (辛), Ren (壬) and Gui (癸). 12 Earthly Branches are 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).

Twelve Earthly Branches and 12 Chinese Zodiac

Zi-Rat, Chou-Tiger, Yin-Tiger, Chen-Dragon, Si-Snake, Wu-Hose, Wei-Goat, Shen-Monkey, You-Rooster, Xu-Dog, Hai-Pig

Heavenly Stems and Earthly Branches and Yin Yang

Heavenly Stems Jia, Bing, Wu, Geng, Ren belong to Yang.
Earthly Branches Zi, Yin, Chen, Wu, Shen, Xu belong to Yang.
They all have meanings of increase, prosperousness and strength.

Heavenly Stems Yi, Ding, Ji, Xin, Gui belong to Yin.
Earthly Branches Chou, Mao, Si, Wei, You, Hai belong to Yin.
They have meanings of decrease, decline and shrink.

Heavenly Stems and Earthly Branches and Five Elements

10 Heavenly Stems and Five Elements
Jia and Yi belong to Wood element. Jia is Yang Wood and Yi is Yin Wood;
Bing and Ding belong to Fire Element. Bing is Yang Fire and Ding is Yin Fire;
Wu and Ji belong to Earth Element. Wu is Yang Earth and Ji is Yin Earth;
Geng and Xin belong to Metal Element. Geng is Yang Metal and Yin is Yin Metal.
Ren and Gui belong to Water Element. Ren is Yang Water and Gui is Yin Water.

12 Earthly Branches and Five Elements
Yin and Mao belong to Wood element. Yin is Yang Wood and Mao is Yin Wood;
Si and Wu belong to Fire Element. Si is Yang Fire and Wu is Yin Fire;
Shen and You belong to Metal Element. Shen is Yang Metal and You is Yin Metal.
Zi and Hai belong to Water Element. Zi is Yang Water and Hai is Yin Water.
Chen, Xu, Chou and Wei belong to Earth Element. Chen and Xu are Yang Earth. Chou and Wei are Yin Earth.

How Does Heavenly Stems and Earth Branches Combine with Each Other?

Combination Rules: Yang Heavenly Stems Match with Yang Earthly Branches. Yin Heavenly Stems Match with Yin Earthly Branches.
Heavenly Stems
Earthly Branches
Jia Yi Bing Ding Wu Ji Geng Xin Ren Gui
Zi Jia Zi   Bing Zi   Wu Zi   Geng Zi   Ren Zi  
Chou   Yi Chou   Ding Chou   Ji Chou   Xin Chou   Gui Chou
Yin Jia Yin   Bing Yin   Wu Yin   Geng Yin   Ren Yin  
Mao   Ji Mao   Ding Mao   Ji Mao   Xin Mao   Gui Mao
Chen Jia Chen   Bing Chen   Wu Chen   Geng Chen   Ren Chen  
Si   Ji Si   Ding Si   Ji Si   Xin Si   Gui Si
Wu Jia Wu   Bing Wu   Wu Wu   Geng Wu   Ren Wu  
Wei   Ji Wei   Ding Wei   Ji Wei   Xin Wei   Gui Wei
Shen Jia Shen   Bing Shen   Wu Shen   Geng Shen   Ren Shen  
You   Ji You   Ding You   Ji You   Xin You   Gui You
Xu Jia Xu   Bing Xu   Wu Xu   Geng Xu   Ren Xu  
Hai   Ji Hai   Ding Hai   Ji Hai   Xin Hai   Gui Hai

60-Year Cycle

The ten heavenly stems and the twelve earthly branches combine with one another and form 60 basic cycles in a fixed pattern, which is called the stem-branch calendar. The invention of heavenly stems and earthly branches has a far-reaching influence. So far, Heavenly Stems and Earthly Branches are still widely used in China for calendar, astrology, calculation, naming and other aspects.
1 2 3 4 5 6 7 8 9 10
Jia-Zi (Metal Rat) Yi-Chou (Metal Ox) Bing-Yin (Fire Tiger) Ding-Mao (Fire Rabbit) Wu-Chen (Wood Dragon) Ji-Si (Wood Snake) Geng-Wu (Earth Horse) Xin-Wei (Earth Goat) Ren-Shen (Metal Monkey) Gui-You (Metal Rooster)
11 12 13 14 15 16 17 18 19 20
Jia-Xu (Fire Dog) Yi-hai (Fire Pig) Bing-Zi (Water Rat) Ding-Chou (Water Ox) Wu-Yin (Earth Tiger) Ji-Mao (Earth Rabbit) Geng-Chen (Metal Dragon) Xin-Si (Metal Snake) Ren-Wu (Wood Horse) Gui-Wei (Wood Goat)
21 22 23 24 25 26 27 28 29 30
Jia-Shen (Water Monkey) Yi-You (Water Rooster) Bing-Xu(Earth Dog) Ding-Hai (Earth Pig) Wu-Zi (Fire Tiger) Ji-Chou (Fire Ox) Geng-Yin (Wood Tiger) Xin-Mao (Wood Rabbit) Ren-Chen (Water Dragon) Gui-Si(Water Snake)
31 32 33 34 35 36 37 38 39 40
Jia-Wu (Metal Horse) Yi-Wei (Metal Goat) Bing-Shen (Fire Monkey) Ding-You (Fire Rooster) Wu-Xu(Wood Dog) Ji-Hai (Wood Pig) Geng-Zi (Earth Rat) Xin-Chou (Earth Ox) Ren-Yin (Metal Tiger) Gui-Mao (Metal Rabbit)
41 42 43 44 45 46 47 48 49 50
Jia-Chen (Fire Dragon) Yi-Si (Fire Snake) Bing-Wu (Water Horse) Ding-Wei (Water Goat) Wu-Shen (Earth Monkey) Ji-You (Earth Rooster) Geng-Xu (Metal Dog) Xin-Hai (Metal Pig) Ren-Zi (Wood Rat) Gui-Chou (Wood Ox)
51 52 53 54 55 56 57 58 59 60
Jia-Yin (Water Tiger) Yi-Mao (Eater Rabbit) Bing-Chen (Earth Dragon) Ding-Si (Earth Snake) Wu-Wu (Fire Horse) Ji-Wei(Fire Goat) Geng-Shen (Wood Monkey) Xin-You (Wood Rooster) Ren-Xu (Water Dog) Gui-Hai (Water Pig)

Heavenly Stems and Earth Branches to Mark Time

Shi Chen
Earth Branches
Hour Jia Or Ji Day (Hour) Yi or Geng (Hour) Bing or Xin Day (Hour) Ding or Ren Day (Hour) Wu or Gui Day (Hour)
Zi Hour 23:00-01:00 Jia Zi Bing Zi Wu Zi Geng Zi Ren Zi
Chou Hour 01:00-03:00 Yi Chou Ding Chou Ji Chou Xin Chou Gui Chou
Yin Hour 03:00-05:00 Bing Yin Wu Yin Geng Yin Ren Yin Jia Yin
Mao Hour 05:00-07:00 Ding Mao Ji Mao Xin Mao Gui Mao Yi Mao
Chen Hour 07:00-09:00 Wu Chen Geng Chen Ren Chen Jia Chen Bing Chen
Si Hour 09:00-11:00 Ji Si Xin Si Gui Si Yi Si Ding Si
Wu Hour 11:00-13:00 Geng Wu Ren Wu Jia Wu Bing Wu Wu Wu
Wei Hour 13:00-15:00 Xin Wei Gui Wei Yi Wei Ding Wei Ji Wei
Shen Hour 15:00-17:00 Ren Shen Jia Shen Bing Shen Wu Shen Geng Shen
You Hour 17:00-19:00 Gui You Yi You Ding You Ji You Xin You
Xu Hour 19:00-21:00 Jia Xu Bing Xu Wu Xu Geng Xu Ren Xu
Hai Hour 21:00-23:00 Yi Hai Ding Hai Ji Hai Xin Hai Gui Hai