Sexagenary cycle explained

The sexagenary cycle, also known as the stems-and-branches or ganzhi (Chinese: 干支|gānzhī), is a cycle of sixty terms, each corresponding to one year, thus a total of sixty years for one cycle, historically used for recording time in China and the rest of the East Asian cultural sphere and Southeast Asia.[1] [2] It appears as a means of recording days in the first Chinese written texts, the Shang oracle bones of the late second millennium BC. Its use to record years began around the middle of the 3rd century BC. The cycle and its variations have been an important part of the traditional calendrical systems in Chinese-influenced Asian states and territories, particularly those of Japan, Korea, and Vietnam, with the old Chinese system still in use in Taiwan, and in Mainland China.[3] In India, the Dai-Ahom (descendants of Dai ethnic minority of Yunnan who migrated to Assam in 13th century) also used the sexagenary cycle known as Lak-Ni.[4] [5]

This traditional method of numbering days and years no longer has any significant role in modern Chinese time-keeping or the official calendar. However, the sexagenary cycle is used in the names of many historical events, such as the Chinese Xinhai Revolution, the Japanese Boshin War, the Korean Imjin War and the Vietnamese Famine of Ất Dậu, Tết Mậu Thân. It also continues to have a role in contemporary Chinese astrology and fortune telling. There are some parallels in this with the current 60-year cycle of the Hindu calendar.

Overview

Each term in the sexagenary cycle consists of two Chinese characters, the first being one of the ten Heavenly Stems of the Shang-era week and the second being one of the twelve Earthly Branches representing the years of Jupiter's duodecennial orbital cycle. The first term jiǎzǐ (Chinese: {{linktext|甲子) combines the first heavenly stem with the first earthly branch. The second term yǐchǒu (Chinese: {{linktext|乙丑) combines the second stem with the second branch. This pattern continues until both cycles conclude simultaneously with guǐhài (Chinese: {{linktext|癸亥), after which it begins again at jiǎzǐ. This termination at ten and twelve's least common multiple leaves half of the combinations—such as jiǎchǒu (Chinese: 甲丑)—unused; this is traditionally explained by reference to pairing the stems and branches according to their yin and yang properties.

This combination of two sub-cycles to generate a larger cycle and its use to record time have parallels in other calendrical systems, notably the Akan calendar.[6]

History

The sexagenary cycle is attested as a method of recording days from the earliest written records in China, records of divination on oracle bones, beginning .[7] Almost every oracle bone inscription includes a date in this format. This use of the cycle for days is attested throughout the Zhou dynasty and remained common into the Han period for all documentary purposes that required dates specified to the day.

Almost all the dates in the Spring and Autumn Annals, a chronological list of events from 722 to 481 BC, use this system in combination with regnal years and months (lunations) to record dates. Eclipses recorded in the Annals demonstrate that continuity in the sexagenary day-count was unbroken from that period onwards. It is likely that this unbroken continuity went back still further to the first appearance of the sexagenary cycle during the Shang period.

The use of the sexagenary cycle for recording years is much more recent. The earliest discovered documents showing this usage are among the silk manuscripts recovered from Mawangdui tomb 3, sealed in 168 BC. In one of these documents, a sexagenary grid diagram is annotated in three places to mark notable events. For example, the first year of the reign of Qin Shi Huang (Undetermined: 秦始皇), 246 BC, is noted on the diagram next to the position of the 60-cycle term yǐ-mǎo (Undetermined: 乙卯, 52 of 60), corresponding to that year. Use of the cycle to record years became widespread for administrative time-keeping during the Western Han dynasty (202 BC – 8 AD). The count of years has continued uninterrupted ever since: the year 1984 began the present cycle (a Undetermined: 甲子jiǎ-zǐ year), and 2044 will begin another. Note that in China the new year, when the sexagenary count increments, is not January 1, but rather the lunar new year of the traditional Chinese calendar. For example, the ji-chou Undetermined: 己丑 year (coinciding roughly with 2009) began on January 26, 2009. (However, for astrology, the year begins with the first solar term "Lìchūn" (Undetermined: 立春), which occurs near February 4.)

In Japan, according to Nihon shoki, the calendar was transmitted to Japan in 553. But it was not until the Suiko era that the calendar was used for politics. The year 604, when the Japanese officially adopted the Chinese calendar, was the first year of the cycle.[8]

The Korean (Korean: 환갑; 還甲 hwangap) and Japanese tradition (Japanese: 還暦 kanreki) of celebrating the 60th birthday (literally 'return of calendar') reflects the influence of the sexagenary cycle as a count of years.[9]

The Tibetan calendar also counts years using a 60-year cycle based on 12 animals and 5 elements, but while the first year of the Chinese cycle is always the year of the Wood Rat, the first year of the Tibetan cycle is the year of the Fire Rabbit (Undetermined: 丁卯dīng-mǎo, year 4 on the Chinese cycle).[10]

Ten Heavenly Stems

See main article: Celestial Stems.

No.Heavenly
Stem
Ahom Name Chinese
name
Japanese
name
Korean
name
Vietnamese
name
Yin YangWu Xing
Mandarin
(Pinyin)
Cantonese
(Jyutping)
Middle Chinese
(Baxter)
Old Chinese
(Baxter–Sagart)
OnyomiKunyomi with
corresponding kanji
RomanizedHangul
1Chinese: kapjiǎgaap3kæp
  • [k]ˤr[a]p
kō (Japanese: こう)kinoe (Japanese: 木の兄)gapKorean: Vietnamese: giáp|italic=noyangwood
2Chinese: dapjyut3ʔit
  • qrət
otsu (Japanese: おつ)kinoto (Japanese: 木の弟)eulKorean: Vietnamese: ất|italic=noyin
3Chinese: raibǐngbing2pjængX
  • praŋʔ
hei (Japanese: へい)hinoe (Japanese: 火の兄)byeongKorean: Vietnamese: bính|italic=noyangfire
4Chinese: Mueang dīngding1teng
  • tˤeŋ
tei (Japanese: てい)hinoto (Japanese: 火の弟)jeongKorean: Vietnamese: đinh|italic=noyin
5Chinese: plaekmou6muwH
  • m(r)uʔ-s (~ *m(r)uʔ)
bo (Japanese: )tsuchinoe (Japanese: 土の兄)muKorean: Vietnamese: mậu|italic=noyangearth
6Chinese: katgei2kiX
  • k(r)əʔ
ki (Japanese: )tsuchinoto (Japanese: 土の弟)giKorean: Vietnamese: kỷ|italic=noyin
7Chinese: khutgēnggang1kæng
  • kˤraŋ
kō (Japanese: こう)kanoe (Japanese: 金の兄)gyeongKorean: Vietnamese: canh|italic=noyangmetal
8Chinese: rungxīnsan1sin
  • si[n]
shin (Japanese: しん)kanoto (Japanese: 金の弟)sinKorean: Vietnamese: tân|italic=noyin
9Chinese: taorénjam4nyim
  • n[ə]m
jin (Japanese: じん)mizunoe (Japanese: 水の兄)imKorean: Vietnamese: nhâm|italic=noyangwater
10Chinese: kaguǐgwai3kjwijX
  • kʷijʔ
ki (Japanese: )mizunoto (Japanese: 水の弟)gyeKorean: Vietnamese: quý|italic=noyin

Twelve Earthly Branches

See main article: Terrestrial Branches.

No.Earthly
Branch
Chinese
name
Japanese
name
Korean
name
Vietnamese
name
Vietnamese
zodiac
Chinese
zodiac
Corresponding
hours
Mandarin
(Pinyin)
Cantonese
(Jyutping)
Middle Chinese
(Baxter)
Old Chinese
(Baxter–Sagart)
OnyomiKunyomiRomanizedHangul
1Chinese: zi2tsiX
  • [ts]əʔ
shi (Japanese: )ne (Japanese: ね)jaKorean: Vietnamese: tý|italic=noRat (Vietnamese: chuột|italic=no Vietnamese: )Rat (Chinese: )11 p.m. to 1 a.m.
2Chinese: chǒucau2trhjuwX
  • [n̥]ruʔ
chū (Japanese: ちゅう)ushi (Japanese: うし)chukKorean: Vietnamese: sửu|italic=noWater buffalo (Vietnamese: trâu|italic=no Vietnamese: )Ox (Chinese: )1 to 3 a.m.
3Chinese: yínjan4yij
  • [ɢ] (r)ər
in (Japanese: いん)tora (Japanese: とら)inKorean: Vietnamese: dần|italic=noTiger (Vietnamese: hổ|italic=no /Vietnamese: cọp|italic=no Vietnamese: )Tiger (Chinese: )3 to 5 a.m.
4Chinese: mǎomaau5mæwX
  • mˤruʔ
bō (Japanese: ぼう)u (Japanese: )myoKorean: Vietnamese: mão/mẹo|italic=noCat (Vietnamese: mèo|italic=no Vietnamese: )Rabbit (Chinese: )5 to 7 a.m.
5Chinese: chénsan4dzyin
  • [d]ər
shin (Japanese: しん)tatsu (Japanese: たつ)jinKorean: Vietnamese: thìn|italic=noDragon (Vietnamese: rồng|italic=no Vietnamese: )Dragon (Chinese: )7 to 9 a.m.
6Chinese: zi6ziX
  • s-[ɢ]əʔ
shi (Japanese: )mi (Japanese: )saKorean: Vietnamese: tỵ|italic=noSnake (Vietnamese: rắn|italic=no Vietnamese: )Snake (Chinese: )9 to 11 a.m.
7Chinese: ng5nguX
  • [m].qʰˤaʔ
go (Japanese: )uma (Japanese: うま)oKorean: Vietnamese: ngọ|italic=noHorse (Vietnamese: ngựa|italic=no Vietnamese: )Horse (Chinese: )11 a.m. to 1 p.m.
8Chinese: wèimei6mjɨjH
  • m[ə]t-s
mi (Japanese: ) or bi (Japanese: )hitsuji (Japanese: ひつじ)miKorean: Vietnamese: mùi|italic=noGoat (Vietnamese: dê|italic=no Vietnamese: )Goat (Chinese: )1 to 3 p.m.
9Chinese: shēnsan1syin
  • l̥i[n]
shin (Japanese: しん)saru (Japanese: さる)sinKorean: Vietnamese: thân|italic=noMonkey (Vietnamese: khỉ|italic=no Vietnamese: )Monkey (Chinese: )3 to 5 p.m.
10Chinese: yǒujau5yuwX
  • N-ruʔ
yū (Japanese: ゆう)tori (Japanese: とり)yuKorean: Vietnamese: dậu|italic=noRooster (Vietnamese: gà|italic=no Vietnamese: )Rooster (Chinese: )5 to 7 p.m.
11Chinese: seot1swit
  • s.mi[t]
jutsu (Japanese: じゅつ)inu (Japanese: いぬ)sulKorean: Vietnamese: tuất|italic=noDog (Vietnamese: chó|italic=no Vietnamese: )Dog (Chinese: )7 to 9 p.m.
12Chinese: hàihoi6hojX
  • [g]ˤəʔ
gai (Japanese: がい)i (Japanese: )haeKorean: Vietnamese: hợi|italic=noPig (Vietnamese: lợn|italic=no Vietnamese: /Vietnamese: heo|italic=no Vietnamese: )Pig (Chinese: )9 to 11 p.m.
*The names of several animals can be translated into English in several different ways. The Vietnamese Earthly Branches use cat instead of Rabbit.

Sexagenary years

No.Stem-BranchMandarin Chinese PinyinKoreanJapaneseVietnameseAssociationsADBCCurrent Cycle
1甲子jiǎ-zǐgapja 갑자Giáp TýYang Wood Rat4571984
2乙丑yǐ-chǒueulchuk 을축Ất SửuYin Wood Ox5561985
3丙寅bǐng-yínbyeongin 병인Bính DầnYang Fire Tiger6551986
4丁卯dīng-mǎojeongmyo 정묘Đinh MãoYin Fire Rabbit7541987
5戊辰wù-chénmujin 무진Mậu ThìnYang Earth Dragon8531988
6己巳jǐ-sìgisa 기사Kỷ TỵYin Earth Snake9521989
7庚午gēng-wǔgyeongo 경오Canh NgọYang Metal Horse10511990
8辛未xīn-wèisinmi 신미Tân MùiYin Metal Goat11501991
9壬申rén-shēnimsin 임신Nhâm ThânYang Water Monkey12491992
10癸酉guǐ-yǒugyeyu 계유Quý DậuYin Water Rooster13481993
11甲戌jiǎ-xūgapsul 갑술Giáp TuấtYang Wood Dog14471994
12乙亥yǐ-hàieulhae 을해Ât HợiYin Wood Pig15461995
13丙子bǐng-zǐbyeongja 병자Bính TýYang Fire Rat16451996
14丁丑dīng-chǒujeongchuk 정축Đinh SửuYin Fire Ox17441997
15戊寅wù-yínmuin 무인Mậu DầnYang Earth Tiger18431998
16己卯jǐ-mǎogimyo 기묘Kỷ MãoYin Earth Rabbit19421999
17庚辰gēng-chéngyeongjin 경진Canh ThìnYang Metal Dragon20412000
18辛巳xīn-sìsinsa 신사Tân TỵYin Metal Snake21402001
19壬午rén-wǔimo 임오Nhâm NgọYang Water Horse22392002
20癸未guǐ-wèigyemi 계미Quý MùiYin Water Goat23382003
21甲申jiǎ-shēngapsin 갑신Giáp ThânYang Wood Monkey24372004
22乙酉yǐ-yǒueuryu 을유Ất DậuYin Wood Rooster25362005
23丙戌bǐng-xūbyeongsul 병술Bính TuấtYang Fire Dog26352006
24丁亥dīng-hàijeonghae 정해Đinh HợiYin Fire Pig27342007
25戊子wù-zǐmuja 무자Mậu TýYang Earth Rat28332008
26己丑jǐ-chǒugichuk 기축Kỷ SửuYin Earth Ox29322009
27庚寅gēng-yíngyeongin 경인Canh DầnYang Metal Tiger30312010
28辛卯xīn-mǎosinmyo 신묘Tân MãoYin Metal Rabbit31302011
29壬辰rén-chénimjin 임진Nhâm ThìnYang Water Dragon32292012
30癸巳guǐ-sìgyesa 계사Quý TỵYin Water Snake33282013
31甲午jiǎ-wǔgabo 갑오Giáp NgọYang Wood Horse34272014
32乙未yǐ-wèieulmi 을미Ất MùiYin Wood Goat35262015
33丙申bǐng-shēnbyeongsin 병신Bính ThânYang Fire Monkey36252016
34丁酉dīng-yǒujeongyu 정유Đinh DậuYin Fire Rooster37242017
35戊戌wù-xūmusul 무술Mậu TuấtYang Earth Dog38232018
36己亥jǐ-hàigihae 기해Kỷ HợiYin Earth Pig39222019
37庚子gēng-zǐgyeongja 경자Canh TýYang Metal Rat40212020
38辛丑xīn-chǒusinchuk 신축Tân SửuYin Metal Ox41202021
39壬寅rén-yínimin 임인Nhâm DầnYang Water Tiger42192022
40癸卯guǐ-mǎogyemyo 계묘Quý MãoYin Water Rabbit43182023
41甲辰jiǎ-chéngapjin 갑진Giáp ThìnYang Wood Dragon44172024
42乙巳yǐ-sìeulsa 을사Ất TỵYin Wood Snake45162025
43丙午bǐng-wǔbyeongo 병오Bính NgọYang Fire Horse46152026
44丁未dīng-wèijeongmi 정미Đinh MùiYin Fire Goat47142027
45戊申wù-shēnmusin 무신Mậu ThânYang Earth Monkey48132028
46己酉jǐ-yǒugiyu 기유Kỷ DậuYin Earth Rooster49122029
47庚戌gēng-xūgyeongsul 경술Canh TuấtYang Metal Dog50112030
48辛亥xīn-hàisinhae 신해Tân HợiYin Metal Pig51102031
49壬子rén-zǐimja 임자Nhâm TýYang Water Rat5292032
50癸丑guǐ-chǒugyechuk 계축Quý SửuYin Water Ox5382033
51甲寅jiǎ-yíngabin 갑인Giáp DầnYang Wood Tiger5472034
52乙卯yǐ-mǎoeulmyo 을묘Ất MãoYin Wood Rabbit5562035
53丙辰bǐng-chénbyeongjin 병진Bính ThìnYang Fire Dragon5652036
54丁巳dīng-sìjeongsa 정사Đinh TỵYin Fire Snake5742037
55戊午wù-wǔmuo 무오Mậu NgọYang Earth Horse5832038
56己未jǐ-wèigimi 기미Kỷ MùiYin Earth Goat5922039
57庚申gēng-shēngyeongsin 경신Canh ThânYang Metal Monkey6012040
58辛酉xīn-yǒusinyu 신유Tân DậuYin Metal Rooster1602041
59壬戌rén-xūimsul 임술Nhâm TuấtYang Water Dog2592042
60癸亥guǐ-hàigyehae 계해Quý HợiYin Water Pig3582043

Conversion between cyclic years and Western years

As mentioned above, the cycle first started to be used for indicating years during the Han dynasty, but it also can be used to indicate earlier years retroactively. Since it repeats, by itself it cannot specify a year without some other information, but it is frequently used with the Chinese era name (年号; "niánhào") to specify a year.[11] The year starts with the new year of whoever is using the calendar. In China, the cyclic year normally changes on the Chinese Lunar New Year. In Japan until recently it was the Japanese lunar new year, which was sometimes different from the Chinese; now it is January 1. So when calculating the cyclic year of a date in the Gregorian year, one has to consider what their "new year" is. Hence, the following calculation deals with the Chinese dates after the Lunar New Year in that Gregorian year; to find the corresponding sexagenary year in the dates before the Lunar New Year would require the Gregorian year to be decreased by 1.

As for example, the year 2697 BC (or −2696, using the astronomical year count), traditionally the first year of the reign of the legendary Yellow Emperor, was the first year (甲子; jiǎ-zǐ) of a cycle. 2700 years later in 4 AD, the duration equivalent to 45 60-year cycles, was also the starting year of a 60-year cycle. Similarly 1980 years later, 1984 was the start of a new cycle.

Thus, to find out the Gregorian year's equivalent in the sexagenary cycle use the appropriate method below.

  1. For any year number greater than 4 AD, the equivalent sexagenary year can be found by subtracting 3 from the Gregorian year, dividing by 60 and taking the remainder. See example below.
  2. For any year before 1 AD, the equivalent sexagenary year can be found by adding 2 to the Gregorian year number (in BC), dividing it by 60, and subtracting the remainder from 60.
  3. 1 AD, 2 AD and 3 AD correspond respectively to the 58th, 59th and 60th years of the sexagenary cycle.
  4. The formula for years AD is and for years BC is .

The result will produce a number between 0 and 59, corresponding to the year order in the cycle; if the remainder is 0, it corresponds to the 60th year of a cycle. Thus, using the first method, the equivalent sexagenary year for 2012 AD is the 29th year (壬辰; rén-chén), as (2012–3) mod 60 = 29 (i.e., the remainder of (2012–3) divided by 60 is 29). Using the second, the equivalent sexagenary year for 221 BC is the 17th year (庚辰; gēng-chén), as 60- [(221+2) mod 60] = 17 (i.e., 60 minus the remainder of (221+2) divided by 60 is 17).

Examples

Step-by-step example to determine the sign for 1967:

  1. 1967 – 3 = 1964 ("subtracting 3 from the Gregorian year")
  2. 1964 ÷ 60 = 32 ("divide by 60 and discard any fraction")
  3. 1964 – (60 × 32) = 44 ("taking the remainder")
  4. Show one of the Sexagenary Cycle tables (the following section), look for 44 in the first column (No) and obtain Fire Goat (丁未; dīng-wèi).

Step-by-step example to determine the cyclic year of first year of the reign of Qin Shi Huang (246 BC):

  1. 246 + 2 = 248 ("adding 2 to the Gregorian year number (in BC)")
  2. 248 ÷ 60 = 4 ("divide by 60 and discard any fraction")
  3. 248 – (60 × 4) = 8 ("taking the remainder")
  4. 60 – 8 = 52 ("subtract the remainder from 60")
  5. Show one of the Sexagenary Cycle table (the following section), look for 52 in the first column (No) and obtain Wood Rabbit (乙卯; yǐ-mǎo).

A shorter equivalent method

Start from the AD year (1967), take directly the remainder mod 60, and look into column AD of the table "Sexagenary years" (just above).

Remainder is therefore 47 and the AD column says 'Fire Goat' as it should be.

For a BC year: discard the minus sign, take the remainder of the year mod 60 and look into column BC. Applied to year -246, this gives:

When doing these conversions, year 246 BC cannot be treated as −246 AD due to the lack of a year 0 in the Gregorian AD/BC system.----The following tables show recent years (in the Gregorian calendar) and their corresponding years in the cycles:

1804–1923

1924–2043

Sexagenary months

The branches are used marginally to indicate months. Despite there being twelve branches and twelve months in a year, the earliest use of branches to indicate a twelve-fold division of a year was in the 2nd century BC. They were coordinated with the orientations of the Great Dipper, (Undetermined: 建子月: jiànzǐyuè, Undetermined: 建丑月: jiànchǒuyuè, etc.).[12] There are two systems of placing these months, the lunar one and the solar one.

One system follows the ordinary Chinese lunar calendar and connects the names of the months directly to the central solar term (; zhōngqì). The jiànzǐyuè ((Undetermined: )Undetermined: 子月) is the month containing the winter solstice (i.e. the Undetermined: 冬至 Dōngzhì) zhōngqì. The jiànchǒuyuè ((Undetermined: )) is the month of the following zhōngqì, which is Dàhán (Undetermined: 大寒), while the jiànyínyuè ((Undetermined: )Undetermined: 寅月) is that of the Yǔshuǐ (Undetermined: 雨水) zhōngqì, etc. Intercalary months have the same branch as the preceding month.[13] In the other system (Undetermined: 節月; jiéyuè) the "month" lasts for the period of two solar terms (two Undetermined: 氣策 qìcì). The zǐyuè (Undetermined: 子月) is the period starting with Dàxuě (Undetermined: 大雪), i.e. the solar term before the winter solstice. The chǒuyuè (Undetermined: 丑月) starts with Xiǎohán (Undetermined: 小寒), the term before Dàhán (Undetermined: 大寒), while the yínyuè (Undetermined: 寅月) starts with Lìchūn (Undetermined: 立春), the term before Yǔshuǐ (Undetermined: 雨水), etc. Thus in the solar system a month starts anywhere from about 15 days before to 15 days after its lunar counterpart.

The branch names are not usual month names; the main use of the branches for months is astrological. However, the names are sometimes used to indicate historically which (lunar) month was the first month of the year in ancient times. For example, since the Han dynasty, the first month has been jiànyínyuè, but earlier the first month was jiànzǐyuè (during the Zhou dynasty) or jiànchǒuyuè (traditionally during the Shang dynasty) as well.

For astrological purposes stems are also necessary, and the months are named using the sexagenary cycle following a five-year cycle starting in a jiǎ (Undetermined: ; 1st) or (; 6th) year. The first month of the jiǎ or year is a bǐng-yín (Undetermined: 丙寅; 3rd) month, the next one is a dīng-mǎo (Undetermined: 丁卯; 4th) month, etc., and the last month of the year is a dīng-chǒu (Undetermined: 丁丑, 14th) month. The next year will start with a wù-yín (Undetermined: 戊寅; 15th) month, etc. following the cycle. The 5th year will end with a yǐ-chǒu (Undetermined: 乙丑; 2nd) month. The following month, the start of a or jiǎ year, will hence again be a bǐng-yín (3rd) month again. The beginning and end of the (solar) months in the table below are the approximate dates of current solar terms; they vary slightly from year to year depending on the leap days of the Gregorian calendar.

Earthly Branches of the certain monthsSolar termZhongqi (the Middle solar term)Starts atEnds atNames in year of Jia or Ji(Undetermined: /Undetermined: 己年)Names in year of Yi or Geng (Undetermined: /Undetermined: 庚年)Names in year of Bing or Xin (Undetermined: /Undetermined: 辛年)Names in year of Ding or Ren (Undetermined: /Undetermined: 壬年)Names in year of Wu or Gui (Undetermined: /Undetermined: 癸年)
Month of Yin (Undetermined: 寅月) LichunJingzheYushui / 雨水February 4March 6Bingyin / Undetermined: 丙寅月Wuyin / Undetermined: 戊寅月Gengyin / Undetermined: 庚寅月Renyin / Undetermined: 壬寅月Jiayin / Undetermined: 甲寅月
Month of Mao (Undetermined: 卯月)Chunfen / 春分March 6April 5Dingmao / Undetermined: 丁卯月Jimao / Undetermined: 己卯月Xinmao / Undetermined: 辛卯月Guimao / Undetermined: 癸卯月Yimao / Undetermined: 乙卯月
Month of Chen (Undetermined: 辰月)QingmingLixiaGuyu / 谷雨April 5May 6Wuchen / Undetermined: 戊辰月Gengchen / Undetermined: 庚辰月Renchen / Undetermined: 壬辰月Jiachen / Undetermined: 甲辰月Bingchen / Undetermined: 丙辰月
Month of Si (Undetermined: 巳月)LixiaMangzhongXiaoman / 小满May 6June 6Jisi / Undetermined: 己巳月Xinsi / Undetermined: 辛巳月Guisi / Undetermined: 癸巳月Yisi / Undetermined: 乙巳月Dingsi / Undetermined: 丁巳月
Month of Wu (Undetermined: 午月)MangzhongXiaoshuXiazhi / 夏至June 6July 7Gengwu / Undetermined: 庚午月Renwu / Undetermined: 壬午月Jiawu / Undetermined: 甲午月Bingwu / Undetermined: 丙午月Wuwu / Undetermined: 戊午月
Month of Wei (Undetermined: 未月)XiaoshuLiqiuDashu / 大暑July 7August 8Xinwei / Undetermined: 辛未月Guiwei / Undetermined: 癸未月Yiwei / Undetermined: 乙未月Dingwei / Undetermined: 丁未月Jiwei / Undetermined: 己未月
Month of Shen (Undetermined: 申月)LiqiuBailuChushu / 处暑August 8September 8Renshen / Undetermined: 壬申月Jiashen / Undetermined: 甲申月Bingshen / Undetermined: 丙申月Wushen / Undetermined: 戊申月Gengshen / Undetermined: 庚申月
Month of You (Undetermined: 酉月)BailuHanluQiufen / 秋分September 8October 8Guiyou / Undetermined: 癸酉月Yiyou / Undetermined: 乙酉月Dingyou / Undetermined: 丁酉月Jiyou / Undetermined: 己酉月Xinyou / Undetermined: 辛酉月
Month of Xu (Undetermined: 戌月)HanluLidongShuangjiang / 霜降October 8November 7Jiaxu / Undetermined: 甲戌月Bingxu / Undetermined: 丙戌月Wuxu / Undetermined: 戊戌月Gengxu / Undetermined: 庚戌月Renxu / Undetermined: 壬戌月
Month of Hai (Undetermined: 亥月)LidongDaxueXiaoxue / 小雪November 7December 7Yihai / Undetermined: 乙亥月Dinghai / Undetermined: 丁亥月Jihai / Undetermined: 己亥月Xinhai / Undetermined: 辛亥月Guihai / Undetermined: 癸亥月
Month of Zi (Undetermined: 子月)DaxueXiaohanDongzhi / 冬至December 7January 6Bingzi / Undetermined: 丙子月Wuzi / Undetermined: 戊子月Gengzi / Undetermined: 庚子月Renzi / Undetermined: 壬子月Jiazi / Undetermined: 甲子月
Month of Chou (Undetermined: 丑月)XiaohanLichunDahan / 大寒January 6February 4Dingchou / Undetermined: 丁丑月Jichou / Undetermined: 己丑月Xinchou / Undetermined: 辛丑月Guichou / Undetermined: 癸丑月Yichou / Undetermined: 乙丑月

Sexagenary days

Table for sexagenary days
Day
(stem)
Month
(stem)
2-digit year
mod 40
(stem)
Century
(stem)
rowspan="2" Century
(branch)
2-digit year
mod 16
(branch)
Month
(branch)
Day
(branch)
Julian
mod 2
GregorianJulian
mod 4
Gregorian
00 10 20 30 Aug 02 21 23 00 00 07 Nov 00 12 24
01 11 21 31 Sep Oct 06 25 27 21 14 01 13 25
02 12 22 Nov Dec 10 29 31 19 19 05 Apr 02 14 26
03 13 23 14 33 35 03 22 03 Feb Jun 03 15 27
04 14 24 18 37 39 17 10 Aug 04 16 28
05 15 25 01 03 22 01 22 15 15 01 Oct 05 17 29
06 16 26 05 07 26 02 18 15 Dec 06 18 30
07 17 27 Mar 09 11 30 21 06 Mar 07 19 31
08 18 28 Jan Apr May 13 15 34 18 13 Jan May 08 20
09 19 29 Feb Jun Jul 17 19 38 23 01 11 Jul 09 21
Dates with the pale yellow background indicate they are for this year. 17 02 10 22
23 09 Sep 11 23

The table above allows one to find the stem & branch for any given date. For both the stem and the branch, find the N for the row for the century, year, month, and day, then add them together. If the sum for the stems' N is above 10, subtract 10 until the result is between 1 and 10. If the sum for the branches' N is above 12, subtract 12 until the result is between 1 and 12.

For any date before October 15, 1582, use the Julian century column to find the row for that century's N. For dates after October 15, 1582, use the Gregorian century column to find the century's N. When looking at dates in January and February of leap years, use the bold & italic Feb and Jan.

Examples

Algorithm for mental calculation

SB=(y+c+m+day)\bmod60

S=SB\bmod10,B=SB\bmod12

y=(year(\bmod400)\bmod80(\bmod12) x 5+\left\lfloor

year(\bmod400)\bmod80
4

\right\rfloor)\bmod60

c=\left\lfloor

year
400

\right\rfloor-\left\lfloor

year
100

\right\rfloor+10

for Gregorian calendar and

c=8

for Julian calendar.

m=(month+1)\bmod2 x 30+\left\lfloor{0.6 x (month+1)-3}\right\rfloor-i


i=5

for Jan or Feb in a common year and

i=6

in a leap year.
MonthJan
13
Feb
14
Mar
03
Apr
04
May
05
Jun
06
Jul
07
Aug
08
Sep
09
Oct
10
Nov
11
Dec
12
m0031−1300031013203330434
Leap year−130

m=\left\lfloor{30.6 x (month+1)}- 3\right\rfloor\bmod60-i

y = 5 x (720–719) + [1/4] = 5

c = 8

m = 30 + [0.6 x 15 – 3] – 5 = 31

d = 22

SB = 5 + 8 + 31 + 22 – 60 = 6

S = B = 6, 己巳

y = 5 x (240–210) + [30/4] = 5 x 6 + 7 = 37

c = 8

m = 0 + [0.6 x 12 – 3] = 4

d = 1

SB = 37 + 8 + 4 + 1 = 50

S = 0, B = 2, 癸丑

y = 5 x (1912–1920) + [-8/4] + 60 = 18

c = 4 – 19 + 10 = -5

m = 30 + [0.6 x 15 – 3] – 6 = 30

d = 18

SB = 18 – 5 + 30 + 18 – 60 = 1

S = B = 1, 甲子

y = 5 x (1949–1920) + [29/4] = 5 x 5 + 7 = 32

c = -5

m = 30 + [0.6 x 11 -3] = 33

d = 1

SB = 32 – 5 + 33 + 1 – 60 = 1

S = B = 1, 甲子

Gregorian
17
24
15
22

20
18


23
16


21
19

Centuries
Julian 01 00
Dates Mar
Jan


Nov
Dec


Sep
Oct


Aug



Feb
Jun
Jul

Jan
Apr
May
Feb
Years of the century
01
11
21
31
02
12
22

03
13
23

04
14
24

05
15
25

06
16
26

07
17
27

08
18
28

09
19
29

10
20
30

天干
Heavenly stems A B C D E F G H I J 00 02 21 23 40 42 61 63 80 82
B C D E F G H I J A 04 06 25 27 44 46 65 67 84 86
C D E F G H I J A B 08 10 29 31 48 50 69 71 88 90
D E F G H I J A B C 12 14 33 35 52 54 73 75 92 94
E F G H I J A B C D 16 18 37 39 56 58 77 79 96 98
F G H I J A B C D E 01 03 20 22 41 43 60 62 81 83
G H I J A B C D E F 05 07 24 26 45 47 64 66 85 87
H I J A B C D E F G 09 11 28 30 49 51 68 70 89 91
I J A B C D E F G H 13 15 32 34 53 55 72 74 93 95
J A B C D E F G H I 17 19 36 38 57 59 76 78 97 99
地支 干支纪日速查表
Earthly branches A B C D E F G H I J K L 00 07 16 23 32 39 48 55 64 71 80 87 96
B C D E F G H I J K L A 14 30 46 62 78 94
C D E F G H I J K L A B 05 21 37 53 69 85
D E F G H I J K L A B C 03 12 19 28 35 44 51 60 67 76 83 92 99
E F G H I J K L A B C D 10 26 42 58 74 90
F G H I J K L A B C D E 01 17 33 49 65 81 97
G H I J K L A B C D E F 08 15 24 31 40 47 56 63 72 79 88 95
H I J K L A B C D E F G 06 22 38 54 70 86
I J K L A B C D E F G H 13 29 45 61 77 93
J K L A B C D E F G H I 04 11 20 27 36 43 52 59 68 75 84 91
K L A B C D E F G H I J 02 18 3450 66 82 98
L A B C D E F G H I J K 09 25 41 57 73 89
Dates 01
13
25
02
14
26
03
15
27
04
16
28
05
17
29
06
18
30
07
19
31
08
20

09
21

10
22

11
23

12
24

Years of the century
Mar
Jan

Dec

Oct

Aug
Feb
Jun
Apr
Feb

Nov

Sep

Jul
Jan
May
Gregorian 15
18



21


24
17



20
23
16
19



22
Centuries
Julian 02 01 00 03

Sexagenary hours

Table for sexagenary hours (5-day cycle)
Stem of the dayZǐ hour
Undetermined: 子时
23:00–1:00
Chǒu hour
Undetermined: 丑时
1:00–3:00
Yín hour
Undetermined: 寅时
3:00–5:00
Mǎo hour
Undetermined: 卯时
5:00–7:00
Chén hour
Undetermined: 辰时
7:00–9:00
Sì hour
Undetermined: 巳时
9:00–11:00
Wǔ hour
Undetermined: 午时
11:00–13:00
Wèi hour
Undetermined: 未时
13:00–15:00
Shēn hour
Undetermined: 申时
15:00–17:00
Yǒu hour
Undetermined: 酉时
17:00–19:00
Xū hour
Undetermined: 戌时
19:00–21:00
Hài hour
Undetermined: 亥时
21:00–23:00
Jia or Ji day
(Undetermined: 甲/己)
1 Undetermined: 甲子2Undetermined: 乙丑3 Undetermined: 丙寅4 Undetermined: 丁卯5 Undetermined: 戊辰6 Undetermined: 己巳7 Undetermined: 庚午8 Undetermined: 辛未9 Undetermined: 壬申10 Undetermined: 癸酉|11 Undetermined: 甲戌12 Undetermined: 乙亥
Yi or Geng day
(Undetermined: 乙/庚)
13 Undetermined: 丙子14 Undetermined: 丁丑15 Undetermined: 戊寅16 Undetermined: 己卯17 Undetermined: 庚辰18 Undetermined: 辛巳19 Undetermined: 壬午20 Undetermined: 癸未21 Undetermined: 甲申22 Undetermined: 乙酉23 Undetermined: 丙戌24 Undetermined: 丁亥
Bing or Xin day
(Undetermined: 丙/辛)
25 Undetermined: 戊子26 Undetermined: 己丑27 Undetermined: 庚寅28 Undetermined: 辛卯29 Undetermined: 壬辰30 Undetermined: 癸巳31 Undetermined: 甲午32 Undetermined: 乙未33 Undetermined: 丙申34 Undetermined: 丁酉35 Undetermined: 戊戌36 Undetermined: 己亥
Ding or Ren day
(Undetermined: 丁/壬)
37 Undetermined: 庚子38 Undetermined: 辛丑39 Undetermined: 壬寅40 Undetermined: 癸卯41 Undetermined: 甲辰42 Undetermined: 乙巳43 Undetermined: 丙午44 Undetermined: 丁未45 Undetermined: 戊申46 Undetermined: 己酉47 Undetermined: 庚戌48 Undetermined: 辛亥
Wu or Gui day
(Undetermined: 戊/癸)
49 Undetermined: 壬子50 Undetermined: 癸丑51 Undetermined: 甲寅52 Undetermined: 乙卯53 Undetermined: 丙辰54 Undetermined: 丁巳55 Undetermined: 戊午56 Undetermined: 己未57 Undetermined: 庚申58 Undetermined: 辛酉59 Undetermined: 壬戌60 Undetermined: 癸亥

See also

References

Sources

External links

Notes and References

  1. Encyclopedia: Louis-Frédéric . Nussbaum . Louis-Frédéric . Käthe . Roth . 2005 . Jikkan-jūnishi . Japan Encyclopedia . 420. 9780674017535 .
  2. For non-mathematical readers, a simple explanation for the number "60" in the 60-year cycle of the Lunar calendar can be found in .
  3. For example, the annual Lunar New Year's Eve Chunwan gala has continued to announce the sexagenary term of the upcoming year (庚子, gengzi for 2020).
  4. "...the Ahom reckoned time by means of a sexa-genary cycle"
  5. "..migration from Mong Mao in Yunnan into Mungdunshunkhām..."
  6. For the Akan calendar, see .
  7. Book: Selin, Helaine. Mathematics Across Cultures: The History of Non-Western Mathematics. 2012-12-06. Springer Science & Business Media. 978-94-011-4301-1. 390. en.
  8. Web site: National Diet Library . Calendar History; the Source . https://web.archive.org/web/20130106054946/http://www.ndl.go.jp/koyomi/e/history/02_index1.html . January 6, 2013 . January 1, 2013.
  9. Encyclopedia: Encyclopedia of Shinto . Kanreki . January 1, 2013.
  10. Book: Chattopadhyaya, Alaka . 1999 . Atisa and Tibet: Life and Works of Dipamkara Srijnana in relation to the history and religion of Tibet . 566–568. Motilal Banarsidass Publ. . 9788120809284 .
  11. Web site: Mathematics of the Chinese calendar . Aslaksen . Helmer . July 17, 2010 . PDF . en . www.math.nus.edu.sg/aslaksen . Department of Maths, National University of Singapore . December 12, 2011 . https://web.archive.org/web/20060424100637/http://www.math.nus.edu.sg/aslaksen/calendar/chinese.shtml . April 24, 2006 . dead . mdy-all .
  12. . . Tokyo . ja:建す.
  13. Book: zh:新唐書 . Xīn Tángshū . New Book of Tang. Records part 6 . zh:本紀第六 肅宗 代宗 . https://zh.wikisource.org/wiki/%E6%96%B0%E5%94%90%E6%9B%B8/%E5%8D%B7006 . .
  14. Book: Conflicting Memories: Tibetan History under Mao Retold. 2020-09-07. BRILL. 978-90-04-43324-3. 640. en.