The sexagenary cycle: all sixty stem-branch years
Ten heavenly stems (天干) run against twelve earthly branches (地支). Both advance by one each year, so the pair returns to its starting point after sixty years rather than after 120 — the cycle that gives 還暦 its name, and that puts 甲子 on 1924, 1984 and 2044 alike.
The ten stems
| Position | Stem | Romanised | Element | Polarity | Vietnamese |
|---|---|---|---|---|---|
| Stem 1 | 甲 | Jia | Wood (木) | Yang | Giáp |
| Stem 2 | 乙 | Yi | Wood (木) | Yin | Ất |
| Stem 3 | 丙 | Bing | Fire (火) | Yang | Bính |
| Stem 4 | 丁 | Ding | Fire (火) | Yin | Đinh |
| Stem 5 | 戊 | Wu | Earth (土) | Yang | Mậu |
| Stem 6 | 己 | Ji | Earth (土) | Yin | Kỷ |
| Stem 7 | 庚 | Geng | Metal (金) | Yang | Canh |
| Stem 8 | 辛 | Xin | Metal (金) | Yin | Tân |
| Stem 9 | 壬 | Ren | Water (水) | Yang | Nhâm |
| Stem 10 | 癸 | Gui | Water (水) | Yin | Quý |
The twelve branches
| Position | Branch | Romanised | Animal | Vietnamese |
|---|---|---|---|---|
| Branch 1 | 子 | Zi | Rat (鼠) | Tý |
| Branch 2 | 丑 | Chou | Ox (牛) | Sửu |
| Branch 3 | 寅 | Yin | Tiger (虎) | Dần |
| Branch 4 | 卯 | Mao | Rabbit (兔) | Mão |
| Branch 5 | 辰 | Chen | Dragon (龙) | Thìn |
| Branch 6 | 巳 | Si | Snake (蛇) | Tỵ |
| Branch 7 | 午 | Wu | Horse (马) | Ngọ |
| Branch 8 | 未 | Wei | Goat (羊) | Mùi |
| Branch 9 | 申 | Shen | Monkey (猴) | Thân |
| Branch 10 | 酉 | You | Rooster (鸡) | Dậu |
| Branch 11 | 戌 | Xu | Dog (狗) | Tuất |
| Branch 12 | 亥 | Hai | Pig (猪) | Hợi |
The sixty combinations
Because the two lists advance together, a stem in an odd position can only ever meet a branch in an odd position. Half the 120 conceivable pairings therefore never occur, and the sixty that do are these.
| Position | Stem-branch | Romanised | Element and animal | Can chi | Years |
|---|---|---|---|---|---|
| Cycle year 1 | 甲子 | Jia-Zi | Yang Wood Rat | Giáp Tý | 1924, 1984, 2044 |
| Cycle year 2 | 乙丑 | Yi-Chou | Yin Wood Ox | Ất Sửu | 1925, 1985, 2045 |
| Cycle year 3 | 丙寅 | Bing-Yin | Yang Fire Tiger | Bính Dần | 1926, 1986, 2046 |
| Cycle year 4 | 丁卯 | Ding-Mao | Yin Fire Rabbit | Đinh Mão | 1927, 1987, 2047 |
| Cycle year 5 | 戊辰 | Wu-Chen | Yang Earth Dragon | Mậu Thìn | 1928, 1988, 2048 |
| Cycle year 6 | 己巳 | Ji-Si | Yin Earth Snake | Kỷ Tỵ | 1929, 1989, 2049 |
| Cycle year 7 | 庚午 | Geng-Wu | Yang Metal Horse | Canh Ngọ | 1930, 1990, 2050 |
| Cycle year 8 | 辛未 | Xin-Wei | Yin Metal Goat | Tân Mùi | 1931, 1991, 2051 |
| Cycle year 9 | 壬申 | Ren-Shen | Yang Water Monkey | Nhâm Thân | 1932, 1992, 2052 |
| Cycle year 10 | 癸酉 | Gui-You | Yin Water Rooster | Quý Dậu | 1933, 1993, 2053 |
| Cycle year 11 | 甲戌 | Jia-Xu | Yang Wood Dog | Giáp Tuất | 1934, 1994, 2054 |
| Cycle year 12 | 乙亥 | Yi-Hai | Yin Wood Pig | Ất Hợi | 1935, 1995, 2055 |
| Cycle year 13 | 丙子 | Bing-Zi | Yang Fire Rat | Bính Tý | 1936, 1996, 2056 |
| Cycle year 14 | 丁丑 | Ding-Chou | Yin Fire Ox | Đinh Sửu | 1937, 1997, 2057 |
| Cycle year 15 | 戊寅 | Wu-Yin | Yang Earth Tiger | Mậu Dần | 1938, 1998, 2058 |
| Cycle year 16 | 己卯 | Ji-Mao | Yin Earth Rabbit | Kỷ Mão | 1939, 1999, 2059 |
| Cycle year 17 | 庚辰 | Geng-Chen | Yang Metal Dragon | Canh Thìn | 1940, 2000, 2060 |
| Cycle year 18 | 辛巳 | Xin-Si | Yin Metal Snake | Tân Tỵ | 1941, 2001, 2061 |
| Cycle year 19 | 壬午 | Ren-Wu | Yang Water Horse | Nhâm Ngọ | 1942, 2002, 2062 |
| Cycle year 20 | 癸未 | Gui-Wei | Yin Water Goat | Quý Mùi | 1943, 2003, 2063 |
| Cycle year 21 | 甲申 | Jia-Shen | Yang Wood Monkey | Giáp Thân | 1944, 2004, 2064 |
| Cycle year 22 | 乙酉 | Yi-You | Yin Wood Rooster | Ất Dậu | 1945, 2005, 2065 |
| Cycle year 23 | 丙戌 | Bing-Xu | Yang Fire Dog | Bính Tuất | 1946, 2006, 2066 |
| Cycle year 24 | 丁亥 | Ding-Hai | Yin Fire Pig | Đinh Hợi | 1947, 2007, 2067 |
| Cycle year 25 | 戊子 | Wu-Zi | Yang Earth Rat | Mậu Tý | 1948, 2008, 2068 |
| Cycle year 26 | 己丑 | Ji-Chou | Yin Earth Ox | Kỷ Sửu | 1949, 2009, 2069 |
| Cycle year 27 | 庚寅 | Geng-Yin | Yang Metal Tiger | Canh Dần | 1950, 2010, 2070 |
| Cycle year 28 | 辛卯 | Xin-Mao | Yin Metal Rabbit | Tân Mão | 1951, 2011, 2071 |
| Cycle year 29 | 壬辰 | Ren-Chen | Yang Water Dragon | Nhâm Thìn | 1952, 2012, 2072 |
| Cycle year 30 | 癸巳 | Gui-Si | Yin Water Snake | Quý Tỵ | 1953, 2013, 2073 |
| Cycle year 31 | 甲午 | Jia-Wu | Yang Wood Horse | Giáp Ngọ | 1954, 2014, 2074 |
| Cycle year 32 | 乙未 | Yi-Wei | Yin Wood Goat | Ất Mùi | 1955, 2015, 2075 |
| Cycle year 33 | 丙申 | Bing-Shen | Yang Fire Monkey | Bính Thân | 1956, 2016, 2076 |
| Cycle year 34 | 丁酉 | Ding-You | Yin Fire Rooster | Đinh Dậu | 1957, 2017, 2077 |
| Cycle year 35 | 戊戌 | Wu-Xu | Yang Earth Dog | Mậu Tuất | 1958, 2018, 2078 |
| Cycle year 36 | 己亥 | Ji-Hai | Yin Earth Pig | Kỷ Hợi | 1959, 2019, 2079 |
| Cycle year 37 | 庚子 | Geng-Zi | Yang Metal Rat | Canh Tý | 1960, 2020, 2080 |
| Cycle year 38 | 辛丑 | Xin-Chou | Yin Metal Ox | Tân Sửu | 1961, 2021, 2081 |
| Cycle year 39 | 壬寅 | Ren-Yin | Yang Water Tiger | Nhâm Dần | 1962, 2022, 2082 |
| Cycle year 40 | 癸卯 | Gui-Mao | Yin Water Rabbit | Quý Mão | 1963, 2023, 2083 |
| Cycle year 41 | 甲辰 | Jia-Chen | Yang Wood Dragon | Giáp Thìn | 1964, 2024, 2084 |
| Cycle year 42 | 乙巳 | Yi-Si | Yin Wood Snake | Ất Tỵ | 1965, 2025, 2085 |
| Cycle year 43 | 丙午 | Bing-Wu | Yang Fire Horse | Bính Ngọ | 1966, 2026, 2086 |
| Cycle year 44 | 丁未 | Ding-Wei | Yin Fire Goat | Đinh Mùi | 1967, 2027, 2087 |
| Cycle year 45 | 戊申 | Wu-Shen | Yang Earth Monkey | Mậu Thân | 1968, 2028, 2088 |
| Cycle year 46 | 己酉 | Ji-You | Yin Earth Rooster | Kỷ Dậu | 1969, 2029, 2089 |
| Cycle year 47 | 庚戌 | Geng-Xu | Yang Metal Dog | Canh Tuất | 1970, 2030, 2090 |
| Cycle year 48 | 辛亥 | Xin-Hai | Yin Metal Pig | Tân Hợi | 1971, 2031, 2091 |
| Cycle year 49 | 壬子 | Ren-Zi | Yang Water Rat | Nhâm Tý | 1972, 2032, 2092 |
| Cycle year 50 | 癸丑 | Gui-Chou | Yin Water Ox | Quý Sửu | 1973, 2033, 2093 |
| Cycle year 51 | 甲寅 | Jia-Yin | Yang Wood Tiger | Giáp Dần | 1974, 2034, 2094 |
| Cycle year 52 | 乙卯 | Yi-Mao | Yin Wood Rabbit | Ất Mão | 1975, 2035, 2095 |
| Cycle year 53 | 丙辰 | Bing-Chen | Yang Fire Dragon | Bính Thìn | 1976, 2036, 2096 |
| Cycle year 54 | 丁巳 | Ding-Si | Yin Fire Snake | Đinh Tỵ | 1977, 2037, 2097 |
| Cycle year 55 | 戊午 | Wu-Wu | Yang Earth Horse | Mậu Ngọ | 1978, 2038, 2098 |
| Cycle year 56 | 己未 | Ji-Wei | Yin Earth Goat | Kỷ Mùi | 1979, 2039, 2099 |
| Cycle year 57 | 庚申 | Geng-Shen | Yang Metal Monkey | Canh Thân | 1980, 2040, 2100 |
| Cycle year 58 | 辛酉 | Xin-You | Yin Metal Rooster | Tân Dậu | 1981, 2041, 2101 |
| Cycle year 59 | 壬戌 | Ren-Xu | Yang Water Dog | Nhâm Tuất | 1982, 2042, 2102 |
| Cycle year 60 | 癸亥 | Gui-Hai | Yin Water Pig | Quý Hợi | 1983, 2043, 2103 |
How this table is produced, and how it was checked
The pairings are arithmetic, not a lookup: the stem is the year modulo ten and the branch is the year modulo twelve, both offset so that 1984 comes out as 甲子, the first year of the current cycle. This page and the calculator call the same function, so a table here and a number there cannot disagree.
The arithmetic is checked against years whose sexagenary names are part of the historical record rather than against the code's own output — if a function is wrong, its output is wrong consistently.
| Year | Computed here as | Known as |
|---|---|---|
| 1894 | 甲午 (Jia-Wu) | 甲午戰爭 — the First Sino-Japanese War, named for the year |
| 1911 | 辛亥 (Xin-Hai) | 辛亥革命 — the Xinhai Revolution, named for the year |
| 1898 | 戊戌 (Wu-Xu) | 戊戌變法 — the Hundred Days’ Reform, named for the year |
One thing deliberately left out. Vietnam's zodiac assigns a different animal to two of the branches — Mão is the cat rather than the rabbit — so the can chi column above gives the branch name only, and no Vietnamese animal is claimed anywhere on this site until it has been checked against a Vietnamese source.
Which year you belong to
The sexagenary year turns at Lunar New Year, which falls between 21 January and 21 February, so anyone born in January or the first days of February belongs to the previous year's pair — not the one matching their Gregorian birth year. The Lunar New Year table gives that boundary date for every year from 1901 to 2099.
The cycle is also applied to months, days and two-hour periods, and was historically used for all four at once. This site uses it for years only, which is the use that survives in ordinary speech.