Overview
Heavenly Stems and Earthly Branches, known as Ganzhi (干支), is the core chronological and symbolic system of ancient China. It is the underlying foundation of Chinese Zodiac, Five Elements, BaZi, traditional calendar and all folk metaphysics customs.
Without understanding Heavenly Stems and Earthly Branches, it is impossible to systematically learn Chinese zodiac, fate culture and traditional folk customs. It is the most fundamental theoretical system of Chinese traditional culture.
The Ten Heavenly Stems (天干)
| Stem | Chinese | Element | Yin/Yang |
|---|---|---|---|
| Jiǎ | 甲 | Wood | Yang |
| Yǐ | 乙 | Wood | Yin |
| Bǐng | 丙 | Fire | Yang |
| Dīng | 丁 | Fire | Yin |
| Wù | 戊 | Earth | Yang |
| Jǐ | 己 | Earth | Yin |
| Gēng | 庚 | Metal | Yang |
| Xīn | 辛 | Metal | Yin |
| Rén | 壬 | Water | Yang |
| Guǐ | 癸 | Water | Yin |
The Twelve Earthly Branches (地支)
The twelve Earthly Branches are: Zi (子), Chou (丑), Yin (寅), Mao (卯), Chen (辰), Si (巳), Wu (午), Wei (未), Shen (酉), You (酉), Xu (戌), Hai (亥).
Each Branch corresponds to one of the 12 zodiac animals and carries its own Five Elements attribute — making the Branches the bridge between the calendar system and zodiac culture.
The 60 Jiazi Cycle (六十甲子)
How It Works
The 10 Stems and 12 Branches are combined in sequence: Stem 1 + Branch 1, Stem 2 + Branch 2, and so on. Because 10 and 12 have a least common multiple of 60, this produces 60 unique Stem-Branch pairs before the cycle repeats.
The first pair is Jiǎzǐ (甲子) — giving the cycle its name. The 60 Jiazi cycle is used for years, months, days and hours.
Ganzhi for Months, Days & Hours
- Months: The 1st lunar month is always Yín (寅), starting from Lichun. Each subsequent month follows the Branch sequence.
- Days: The 60-day cycle runs continuously, found via the Ten-Thousand-Year Calendar (万年历).
- Hours: Each Chinese "shichen" equals 2 hours, mapped to the 12 Branches:
- Zi hour: 23:00–00:59
- Chou hour: 01:00–02:59
- Yin hour: 03:00–04:59
- ... continuing through to Hai hour: 21:00–22:59
Folk Cultural Functions
- Chronological recording: Ancient official and folk year, month, day, hour documentation
- BaZi framework: The basic structure of Four Pillars destiny calculation
- Zodiac correspondence: Direct mapping to the 12 Chinese Zodiac animals
- Five Elements matching: Combined with elements for fortune analysis and naming
- Date selection: Core standard for traditional auspicious date choosing