What Are Heavenly Stems in Chinese Astrology

Note: The simplified examples below use the Common Era year-ending shortcut. TimeZign's calculator uses the Chinese New Year boundary of each year, so births before that date can map to the previous Heavenly Stem cycle.

What Are the Heavenly Stems

Heavenly Stems, or in Chinese called 天干 (Tiāngān), are a 10-year cycle counting system that has played an important role in Chinese astrology since ancient times. Used together with Earthly Branches — what we know as zodiac animals — to create a 60-year cycle called the Sexagenary Cycle, which is the most complete cycle for calculating destiny according to Chinese astrology.

The Heavenly Stem system is not merely numbers or symbols for counting years, but representatives of various energies and elements believed to influence the lives and personalities of people born in each year. Understanding Heavenly Stems thus helps us see a more profound and detailed overall picture of destiny than looking at zodiac animals alone.

The 10 Heavenly Stems

There are ten characters total, each with specific names and different meanings: Jiǎ (甲), Yǐ (乙), Bǐng (丙), Dīng (丁), Wù (戊), Jǐ (己), Gēng (庚), Xīn (辛), Rén (壬), and Guǐ (癸). Each of these characters relates to different elements and yin-yang energies.

Each stem has specific characteristics that reflect the qualities of people born in each year. For example, Jiǎ (甲), which is Yang Wood, often represents strong and stable growth, like a large tree with deep roots. Meanwhile, Yǐ (乙), which is Yin Wood, represents gentleness and flexibility, like a climbing vine that adapts to its environment.

Relationship to the Five Elements

The heart of Heavenly Stems lies in their relationship with the five elements. Two stems represent each element, divided into yang and yin. Jiǎ and Yǐ are Wood, where Jiǎ is yang — energy that is strong and clearly expressed, while Yǐ is yin — energy that is gentle and flexible.

Bǐng and Dīng are Fire, where Bǐng is yang — fire that is bright and intensely hot like sunlight, while Dīng is yin — fire that is soft and warm like candlelight. Wù and Jǐ are Earth, where Wù is yang — earth that is strong like mountains, while Jǐ is yin — earth that is fertile like planting soil.

Gēng and Xīn are Metal, where Gēng is yang — metal that is strong and firm like steel, while Xīn is yin — metal that is valuable and delicate like gold and gems. Rén and Guǐ are Water, where Rén is yang — water that flows vigorously and is vast like rivers, while Guǐ is yin — water that is quiet and accumulated like rain or dew.

Meaning of Yin-Yang Energy

Yin-yang energy is the heart of Chinese philosophy and astrology. Yang is energy that expresses outwardly, is enthusiastic, strong, and has movement. Meanwhile, yin is energy that turns inward, is calm and quiet, gentle, and has accumulation. Each stem that is yang or yin clearly influences the personality of people born in that year.

People with yang stems tend to be enthusiastic, like to express themselves, and have high energy. Meanwhile, people with yin stems tend to be calm, like to think and plan carefully, and have sensitivity in perceiving things. Knowing whether our stem is yang or yin thus helps us understand ourselves more deeply.

How to Calculate Your Heavenly Stem

Calculating your Heavenly Stem is easy — anyone can do it by looking at the last digit of their birth year in the Common Era calendar. The calculation rule is: years ending in 4 are Jiǎ, years ending in 5 are Yǐ, then cycling through the sequence until years ending in 3 are Guǐ, then cycling back to Jiǎ again.

For example, 1991 ends in 1, making it a Xīn year, which is Yin Metal. Or 2024 ends in 4, making it a Jiǎ year, which is Yang Wood. Knowing your own Heavenly Stem helps us understand our basic characteristics better and can be used beneficially in choosing things that harmonize with our element and energy.