The sexagesimal cycle in China is composed of two series that paired with one another. The 10 Heavenly Stems (十干; pinyin: shi gan) are paired with the 12 Earthly Branches (十二支; pinyin: shi er zhi) giving rise to 60 combinations.

Ten Heavenly Stems

甲 jia3 first
乙 yi3 second
丙 bing3 third
丁 ding1 fourth
戊 wu4 fifth
己 ji3 sixth
庚 geng1 seventh
辛 xin1 eighth
壬 ren2 ninth
癸 gui3 tenth

They can also reprensent ordinal numbers in Chinese.

Twelve Earthly Branches

子 zi3 23-1 rat
丑 chou3 1-3 ox
寅 yin2 3-5 tiger
卯 mao3 5-7 rabbit
辰 chen2 7-9 dragon
巳 si4 9-11 snake
午 wu3 11-13 horse
未 wei4 13-15 ram
申 shen1 15-17 monkey
酉 you3 17-19 rooster
戌 xu1 19-21 dog
亥 hai4 21-23 pig

These can also represent animals of the Chinese Zodiac and hours of the day. Note that the hours in the old fashioned Chinese sense represent two hours on the 24 hour clock.

The Sexagesimal Cycle

 甲子 乙丑 丙寅 丁卯 戊辰 己巳 庚午 辛未 壬申 癸酉 甲戌 乙亥 1 2 3 4 5 6 7 8 9 10 11 12 

 丙子 丁丑 戊寅 己卯 庚辰 辛巳 壬午 癸未 甲申 乙酉 丙戌 丁亥 13 14 15 16 17 18 19 20 21 22 23 24 

 戊子 己丑 庚寅 辛卯 壬辰 癸巳 甲午 乙未 丙申 丁酉 戊戌 己亥 25 26 27 28 29 30 31 32 33 34 35 36 

 庚子 辛丑 壬寅 癸卯 甲辰 乙巳 丙午 丁未 戊申 己酉 庚戌 辛亥 37 38 39 40 41 42 43 44 45 46 47 48 

 壬子 癸丑 甲寅 乙卯 丙辰 丁巳 戊午 己未 庚申 辛酉 壬戌 癸亥 49 50 51 52 53 54 55 56 57 58 59 60 

The sexagesimal cycle is used primarily as a naming convention for years, but also for months, days, and hours. The invention of the Chinese calendar is attributed to Huang Di.

For example the year 2000 was 17th year of the 78th sexagesimal cycle, named GengChen year (庚辰年). Therefore, 2004 is four years after, the 21st year of the 78th sexagesimal cycle, called JiaShen year (甲申年).

The naming of the months, and days is somewhat less used, although they will be shown on Chinese calendars and almanacs.

See also: Chinese calendar