|History of science and|
technology in China
The traditional Chinese calendar (official Chinese name: Rural Calendar (農曆; 农历; Nónglì; "farming calendar"), alternately Former Calendar (舊曆; 旧历; Jiùlì), Traditional Calendar (老曆; 老历; Lǎolì), or Lunar Calendar (陰曆; 阴历; Yīnlì; "yin calendar")) is a lunisolar calendar which reckons years, months and days according to astronomical phenomena. It was first developed during the Qin Dynasty, and is currently defined by GB/T 33661-2017 Calculation and promulgation of the Chinese calendar, which the Standardization Administration of China issued on May 12, 2017.
China now officially uses the Gregorian calendar, but the traditional Chinese calendar still governs traditional activities in China and in overseas Chinese communities, such as the Chinese New Year. It lists the dates of traditional Chinese holidays, and guides people in selecting the most auspicious days for weddings, funerals, moving, or beginning a business.
As with Chinese characters, different variants of this calendar are used in different parts of the Chinese cultural sphere. Korea, Vietnam, and the Ryukyu Islands adopted the calendar completely, where it evolved into Korean, Vietnamese, and Ryukyuan calendars, respectively. The main difference from the traditional Chinese calendar is the use of different meridians, which leads to some astronomical events—and the calendar events based on those—falling on different dates. The traditional Japanese calendar also derived from the Chinese calendar based on a Japanese meridian, but its official use in Japan was abolished in 1873 as part of reforms subsequent to the Meiji Restoration. Calendars in Mongolia and Tibet have absorbed elements from the traditional Chinese calendar, but they are not direct descendants of it.
In this calendar, days begin and end at midnight. Months begin on the day with the new moon. Years begin on the second or third new moon after the winter solstice. The solar terms govern the start and end of each month. Written versions in ancient China[when?] would include information such as the stem-branch of the year and names of each month, including leap months when needed. For each month, there would be characters for whether the month was long (大, containing 30 days) or short (小, containing 29 days); the stem-branches for the first, eleventh, and 21st days; and the date, stem-branch, and time of the solar terms.
Definitions of elements in the traditional Chinese calendar:
The Big Dipper is regarded as the compass in the sky, and the handle's direction decides the season and solar month.
The stars are divided into Three Enclosures and 28 Mansions according to their locations in the sky relative to Ursa Minor at the centre. Each mansion is named with a character that describes the shape of the principal asterism it contains.
The moon moves through about one lunar mansion per day, so the 28 mansions were also used to count days. In the Tang Dynasty, Yuan Tiangang (袁天罡) matched the 28 mansions, seven luminaries and yearly animal signs, yielding combinations such as “horn-wood-flood dragon” (角木蛟).
Several coding systems are used for some special circumstances in order to avoid ambiguity, such as continuous day or year count.
|Stem-branches||Heavenly stems||Earthly branches|
|Wu Xing||Stem, branch||Wu Xing||Stem||-gēng (1⁄10 of day)||Wu Xing||Branch||-shí (dual hour)||-yuè (month)|
|metal||1, 1||9, 9||7, 5||1, 7||9, 3||7, 11||wood||1||jiǎ||甲||19:12||yīgēng||1||water||zǐ||子||00:00||Shíyīyuè (SYY)||十一月|
|2, 2||10, 10||8, 6||2, 8||10, 4||8, 12||2||yǐ||乙||21:36||èrgēng||2||soil||chǒu||丑||02:00||Làyuè (LAY)||臘月|
|fire||3, 3||1, 11||5, 1||3, 9||1, 5||5, 7||fire||3||bǐng||丙||0:00||sāngēng||3||wood||yín||寅||4:00||Zhēngyuè (ZNY)||正月|
|4, 4||2, 12||6, 2||4, 10||2, 6||6, 8||4||dīng||丁||2:24||sìgēng||4||mǎo||卯||6:00||Èryuè (ERY)||二月|
|wood||5, 5||9, 7||7, 3||5, 11||9, 1||7, 9||soil||5||wù||戊||4:48||wǔgēng||5||soil||chén||辰||8:00||Sānyuè (SNY)||三月|
|6, 6||10, 8||8, 4||6, 12||10, 2||8, 10||6||jǐ||己||7:12||morning||6||fire||sì||巳||10:00||Sìyuè (SIY)||四月|
|water||3, 1||1, 9||9, 5||3, 7||1, 3||9, 11||metal||7||gēng||庚||9:36||midmorning||7||wǔ||午||12:00||Wǔyuè (WUY)||五月|
|4, 2||2, 10||10, 6||4, 8||2, 4||10, 12||8||xīn||辛||12:00||noon||8||soil||wèi||未||14:00||Liùyuè (LUY)||六月|
|soil||7, 7||5, 3||3, 11||7, 1||5, 9||3, 5||water||9||rén||壬||14:24||late afternoon||9||metal||shēn||申||16:00||Qīyuè (QIY)||七月|
|8, 8||6, 4||4, 12||8, 2||6, 10||4, 6||10||guì||癸||16:48||evening||10||yǒu||酉||18:00||Bāyuè (BAY)||八月|
China has used the Western hour-minute-second system to divide the day since the Qing dynasty. Before then, several systems of dividing the day were used depending on the era. Systems using multiples of twelve and ten were popular since they could be easily counted and aligned with the celestial stems and earthly branches.
In both old systems and the modern one, days begin and end at midnight although, colloquially, people refer to days beginning at dawn.
As early as the Bronze Age Xia dynasty, days were grouped into nine- or ten-day weeks, called xún (旬). Months were divided into 3 xún. The first 10 days was the early xún (上旬), the middle 10 days was the mid xún (中旬), and the last 9 or 10 days is the late xún (下旬). Japan adopted this pattern, though the 10-day-weeks were called jun (旬). In Korea, it was called sun (순,旬).
The structure of xún lead to work holidays being every five or ten days. During the Han dynasty, officials of the empire were legally required to rest every five days (沐; mù, from 休沐; xiūmù; "wash rest"), which allowed these breaks to happen twice a xún and 5–6 times a month. This was changed to every 10 days in the Tang dynasty. The name of these breaks was changed to huan (澣; 浣, again meaning "wash").
Grouping days into sets of ten is still used today in referring to specific natural events. Three Fu (三伏), a period of 29–30 days which are the hottest of the year, is a term reflecting that it lasts for three xún. After the winter solstice, people traditionally count off 9 sets of 9 days (or 9 late xún) to figure out when winter ends.
The seven-day week was adopted from the Hellenistic system by the 4th century CE, although by which route is not entirely clear. It was again transmitted to China in the 8th century by Manichaeans, via the country of Kang (a Central Asian polity near Samarkand).[a][b] It is the most predominantly used system in modern China.
Months are defined by the time between new moons, which averages to 29 17⁄32 days. Instead of using half-days to balance the months with the lunar cycle, every other month of the year has 29 days (short month, 小月) and the rest have 30 (long month, 大月). Years start on a long month and alternate short-long-short-long until the year ends.
A 12-month-year using this system has only 354 days. Using only 12 months per year would cause significant drift from the tropical year. To fix this, traditional Chinese years alternate a 13-month-year every other year. The 13-month version has the same alternation of long and short months, but adds a 30-day month at the end of the year. Years with 12 months are called common years, and years with 13 months are called long years.
Though most of the above rules applied until the Tang Dynasty, different eras used different systems to keep the lunar and solar years aligned. For example, the synodic month of the Taichu calendar was 29 43⁄81 days. The 7th century Wùyín Yuán Calendar of the Tang dynasty was the first to determine month length by the real synodic month, instead of using the cycling method. Since then, month lengths have been determined by observation and prediction, with few exceptions.[c]
The days of the month are numbered beginning with 1, and the day's number is always written with two characters.
As a convention, history books use days of the month as numbered with the 60 stem-branches. For example:
Because astronomical observation is used to determine month lengths, dates on this calendar correspond to moon phases. The first day of each month is the new moon. In the 7th or 8th day of each month, the first quarter moon is visible in the afternoon and early evening. In the 15th or 16th day of each month, the full moon is visible all night. In the 22nd or 23rd day of each month, the last quarter moon is visible late at night and in the morning.
Since the beginning of the month is determined by the time when the new moon occurs, other countries using this calendar use their own time standards to calculate it. This results in deviations. For instance, the first new moon in 1968 was at UTC Jan 29 16:29. Since North Vietnam used the UTC+7 timezone to calculate their Vietnamese calendar, and South Vietnam used the longitude of Beijing to calculate theirs, North Vietnam started the holiday of Tết at Jan 29 23:29, while South Vietnam started it at Jan 30 00:15. Using this time difference allowed asynchronous attacks in Tet Offensive.
The solar year (歲; 岁; Suì) is the time between winter solstices. The solar year is divided further into 24 solar terms. In ancient China, solar terms were estimated as 1⁄24 of the solar year, or about 15 7⁄32 days. Starting from the 17th century, when the Shixian Calendar of Qing dynasty was adopted, the solar year was determined by the real tropical year instead. The solar terms correspond to intervals of 15° along the ecliptic.
Different version of traditional Chinese calendar might have different average solar year length. One solar year of the Tàichū calendar from 1st century BC is 365 385⁄1539—or 365.25016—days. A solar year of the 13th century Shòushí calendar is 365 97⁄400—or 365.24250—days, the same as the Gregorian calendar. The additional 0.00766-day from the Tàichū calendar leads to a one-day shift every 130.5 years.
Couples of solar terms are climate terms, or solar months. The first of each couple is "pre-climate" (節氣; 节气; Jiéqì), and the second of the each couple is "mid-climate" (中氣; 中气; Zhōngqì). In the list below, the odd numbers are the pre-climates, and the even numbers are the mid-climates.
The solar term system is not suitable for the place between regression line, such as Hongkong, for there must be two summer solstices in a year.
|Year mod 19|
In general, there are 11 or 12 complete months—plus 2 incomplete months which border the winter solstice—in a solar year. The 11 mid-climates except the winter solstice are in the 11 or 12 complete months. The complete months are numbered from 0 to 10, and the incomplete months together are considered to be the 11th month.
The first month without a mid-climate is the leap month or intercalary month. Leap months are numbered using the character for "intercalary", rùn 閏, then the name of the month they follow. In 2017, the intercalary month after month 6 was called Rùn Liùyuè, or "intercalary sixth month" (閏六月). When writing or using shorthand, it was referred to as 6i or 6+. The next intercalary month occurs in 2020 after month 4, so it will be called Rùn Sìyuè (閏四月) and 4i or 4+ will be used as shorthand.
The lunisolar year starts from the first spring month, called Zhēngyuè (正月; "capital month") and ends at the last winter month, called Làyuè (臘月; 腊月; "sacrificial month"). All other months are named for their number in the month order. If a leap month falls after month 11—as it will in 2033—the 11th month will be Shíèryuè (十二月; "twelfth month") and the leap month will be Làyuè.
Years were traditionally numbered after the reign title in Ancient China, but this was no longer used after the founding of the People's Republic of China in 1949. For example, the year from February 8, 2016 to January 27, 2017 was a Bǐngshēn year (丙申年), 12 months or 354 days long.
During a brief period in the Tang Dynasty, the earthly branches were used to mark the months from Dec, 761 to May, 762. Within this period, the year started from the month with Winter Solstice. The first month was Yínyuè instead of Zhēngyuè, the second month was Mǎoyuè, instead of Èryuè; the third was Chényuè instead of Sānyuè, etc.
|Nineteen-year cycle for Chinese calendar|
|Cell: year mod 19 | Column: plus 8 mod 19 | Row: plus 11 mod 19|
|Leap years||Common years|
|Earliest||Leap months and dates of New Year's Day (M: Month | J: January | F: February)||Latest|
In China, age for official use is based on the Gregorian calendar. For traditional use, age is based on the Chinese calendar. For the first year from the birthday, the child is considered one year old. After each New Year's Eve, add one year. "Ring out the old age and ring in the new one (辭舊迎新; 辞旧迎新; cíjiù yíngxīn)" is the literary express of New Year Ceremony. For example, if one's birthday is Làyuè 29th 2013, he is 2 years old at Zhēngyuè 1st 2014. On the other hand, people say months old instead of years old, if someone is too young. It is that the age sequence is "1 month old, 2 months old, ... 10 months old, 2 years old, 3 years old...".
After the actual age (實歲; 实岁) was introduced into China, the Chinese traditional age was referred to as the nominal age (虛歲; 虚岁). Divided the year into two halves by the birthday in the Chinese calendar,[d] the nominal age is 2 older than the actual age in the first half, and the nominal age is 1 older than the actual age in the second half (前半年前虛兩歲，後半年虛一歲; 前半年前虚两岁，后半年虚一岁).[e]
Just as it is awkward to define the birthday of someone born on the 29th of February in the Gregorian calendar, special rules are used for birthdays or other anniversaries during the leap month or on the 30th day.
In the Ancient China, years were numbered from 1 beginning from the year a new emperor ascended the throne, or when the current emperor announced a new era name. The first recorded reign title was Jiànyuán (建元; "era establishment", in 140 BCE), and the last reign title was Xuāntǒng (宣統; 宣统, in 1908 CE). The era system was abolished in 1912 CE, after which the Current Era or Republican era was used. The epoch of the Current Era is just the same as the era name of Emperor Ping of Han, Yuánshí (元始; "era beginning").
The 60 stem-branches have been used to mark the date continually since the Shang Dynasty. Astrologers in this era knew the orbital period of Jupiter is about 4332 days. Since 4332 is 12 * 361, the orbital period of Jupiter was divided into 12 years (歲; 岁; suì) of 361 days each.
The first day of each suì year was called the greatest suì (太歲; 太岁; tàisuì). 361 days is 6 sexagenary cycles with an extra day, so every tàisuì moved one place forward in the stem-branch cycle. The stem-branch of the tàisuì was thus assigned to the whole year. Sometimes there were two taisui in a year, since the 1⁄12 Jovian cycle suì year is shorter than solar year. After about 86 years, a tàisuì was leaped, referred to as being "beyond the star" (超辰; chāochén). In the Eastern Han Dynasty, the chaochen were abolished, and the 60 stem-branches were then used to mark the year continually without leap.
The Stem-branches year number system provided a solution for the unequal length of the reign titles in the era system.
Occasionally, nomenclature similar to that of the Christian era has been used, such as
No reference date is universally accepted. The most popular is the Gregorian Calendar (公曆; 公历; gōnglì).
On January 2, 1912, Sun Yat-sen declared a change to the official calendar and era. In his declaration, January 1, 1912 is called Shíyīyuè 13th, 4609 Huángdì era which assumes an epoch 1st year of 2698 BCE. This declaration was adopted by many overseas Chinese communities outside Southeast Asia such as San Francisco's Chinatown.
In the 17th century, the Jesuits tried to determine what year should be considered the epoch of the Han calendar. In his Sinicae historiae decas prima (first published in Munich in 1658), Martino Martini (1614–1661) dated the ascension of the Yellow Emperor to 2697 BC, but started the Chinese calendar with the reign of Fuxi, which he claimed started in 2952 BCE. Philippe Couplet's (1623–1693) Chronological table of Chinese monarchs (Tabula chronologica monarchiae sinicae; 1686) also gave the same date for the Yellow Emperor. The Jesuits' dates provoked great interest in Europe, where they were used for comparisons with Biblical chronology.
Modern Chinese chronology has generally accepted Martini's dates, except that it usually places the reign of the Yellow Emperor in 2698 BC and omits the Yellow Emperor's predecessors Fuxi and Shennong, who are considered "too legendary to include".
Starting in 1903, radical publications started using the estimated birthdate of the Yellow Emperor as the first year of the Han calendar. Different newspapers and magazines proposed different dates. Jiangsu, for example, counted 1905 as year 4396 (using a year 0 of 2491 BCE), whereas the newspaper Ming Pao (明報; 明报) reckoned 1905 as 4603 (using a year 0 of 2698 BCE). Liu Shipei (劉師培; 1884–1919) created the Yellow Emperor Calendar, now often used to calculate the date, to show the unbroken continuity of the Han race and Han culture from earliest times. Liu's calendar started with the birth of the Yellow Emperor, which he determined to be 2711 BC. There is no evidence that this calendar was used before the 20th century. Liu calculated that the 1900 international expion sent by the Eight-Nation Alliance to suppress the Boxer Rebellion entered Beijing in the 4611th year of the Yellow Emperor.
An astrological epoch in the Chinese calendar is called lìyuán (曆元; 历元). Each lìyuán begins on the optimal start date of the calendar, when a jiǎzǐ (甲子) day is the first day of a lunar month and the dark moon and winter solstice are at exactly midnight (日得甲子夜半朔旦冬至). Making this definition more specific, such as using a jiǎzǐ day with an auspicious star sign, lead to the definition of a supreme lìyuán (Chinese: 上元; pinyin: shàngyuán). The continuous year based on the supreme lìyuán is shàngyuán jīnián (上元積年; 上元积年). The addition of factors added to calculation of the supreme lìyuán caused the shàngyuán jīnián to become a huge number, leading to its removal from the Shòushí calendar.
Shao Yong (邵雍 1011–1077), a philosopher, cosmologist, poet, and historian who greatly influenced the development of Neo-Confucianism in China, introduced a time system in his Book of supreme world ordering principles (皇極經世; 皇极经世; Huángjíjīngshì).
In his time system, 1 yuán (元; "origin"), which contains 129,600 years, is a lifecycle of the world. Each yuán is divided into 12 huì (會; 会; "gathering") of 10,800 years. Each huì is divided into 30 yùn (運; 运; "fate") of 360 years, and each yùn is divided into 12 shì (世; "generation") of 30 years. Shào's Huángjíjīngshì recorded the history of the timing system from the first year of the 180th yùn or 2149th shì (HYSN 0630-0101, 2577 BC) and marked the year with the reign title from the Jiǎchénnián of the 2156th shì (HYSN 0630-0811, 2357 BC, Tángyáo 1, 唐堯元年; 唐尧元年). According to this time system, January 31, 2014 is HYSN/YR 0712-1001/01-01.
Since the ratios are the same between yuán-huì-yùn-shì and years-months-days-double hours, the yuán-huì-yùn-shì is called the major trend or the numbers of the heaven, and the years-months-days-double hours is called the minor trend or the numbers of the earth. The minor trend of the time of a person's birth has been adapted into a fortune-telling method called Bāzì, or Four Pillars of Destiny, using the stem-branch of each of the four aspects. For example, the Bāzì of the Qianlong Emperor is Xīnmǎo (辛卯) year, Dīngyǒu(丁酉) month, Gēngwǔ (庚午) day, Bǐngzǐ (丙子) hour.
The table below shows the kinds of year number system along with correspondences to the Western (Gregorian) calendar. Alternatively, see this larger table of the full 60-year cycle.
|Year in cycle||s,b||Gānzhī (干支)||Year of the...||Gregorian year||YROC[table 1]||HYSN[table 2]||AH[table 3]||Begins|
|27||7,3||gēngyín (庚寅)||Metal Tiger||2010||99||0712-0927||4707||February 14|
|28||8,4||xīnmǎo (辛卯)||Metal Rabbit||2011||100||0712-0928||4708||February 3|
|29||9,5||rénchén (壬辰)||Water Dragon||2012||101||0712-0929||4709||January 23|
|30||10,6||guǐsì (癸巳)||Water Snake||2013||102||0712-0930||4710||February 10|
|31||1,7||jiǎwǔ (甲午)||Wood Horse||2014||103||0712-1001||4711||January 31|
|32||2,8||yǐwèi (乙未)||Wood Goat||2015||104||0712-1002||4712||February 19|
|33||3,9||bǐngshēn (丙申)||Fire Monkey||2016||105||0712-1003||4713||February 8|
|34||4,10||dīngyǒu (丁酉)||Fire Rooster||2017||106||0712-1004||4714||January 28|
|35||5,11||wùxū (戊戌)||Earth Dog||2018||107||0712-1005||4715||February 16|
|36||6,12||jǐhài (己亥)||Earth Pig||2019||108||0712-1006||4716||February 5|
In the Sinosphere, the traditional festivals are calculated using the date or solar terms, and are considered auspicious.
|Festival name (Chinese)||Festival name (English)||Occurs on...||Chinese date (modern)||Chinese date (Han Dynasty)||Gregorian date||Remark|
|Sacrifice Day||Fixed date||00-08
|The third Xu (戌) day after the Winter Solstice||2017-01-05|
|Preliminary Eve||Fixed date||00-23/00-24
|the cleanup day before New Year's Week|
|New Year's Eve||Fixed date||01-00
the last day of the year, Làyuè 29 or 30
|2017-01-27||a statutory holiday|
|New Year's Day||Fixed date||01-01
The first day of the year, Zhēngyuè 1
|2017-01-28||a statutory holiday|
|The first full moon of the year||2017-02-11||Also called as Yuanxiao (the night of the first full moon), an annual carnival in ancient China|
|Outing Festival||Fixed date||03-03
|The first Si (巳) day of Sanyue||2017-03-30||a version of Qingmin Festival, The origin of Thailand water splashing festival|
|Buddha's Birthday||Fixed date||04-08
|2017-05-03||a statutory holiday in Hong Kong SAR|
|Dragon Boat Festival||Fixed date||05-05
|The First Wu (午) day of Wuyue||2017-05-30||a statutory holiday|
|Star Festival||Fixed date||07-07
|2017-08-28||Ingenuity Maiden's Day|
|Ghost Festival||Fixed date||07-15
|The full moon at the mid-year||2017-09-05||the worship of ancestors|
|Mid-Autumn Festival||Fixed date||08-15
|The full moon at the mid-autumn||2017-10-04||Reunion Day, a statutory holiday|
|Climbing Festival||Fixed date||09-09
|2017-10-28||Regarded as Elder's Day in China
a statutory holiday in Hong Kong SAR
|Shiyue Worship||Fixed date||10-01
|The New Year's Day of Qin Calendar||2017-11-18||Issue Royal calendar (almanac) for the following year.|
|Spirit Festival||Fixed date||10-15
|The first full moon in Qin calendar||2017-12-02||the worship of worthy|
|Beginning of Spring||Solar term (variable date)||The day that the sun reaches 315° celestial longitude||Zhēngyuè 8
about February 3
|The day of the Stimulation of Agriculture|
|Cold Food Festival||Solar term (variable date)||The 105th day after the Winter Solstice||Sānyuè 7, 2017
about April 3
|The fast before the worship of ancestors at Qingming Festival.|
|Qingming Festival||Solar term (variable date)||The day that the sun reaches 15° celestial longitude||Sānyuè 8, 2017
about April 4
|The day of the worship of ancestors, a statutory holiday|
|Winter Solstice||Solar term (variable date)||The shortest day of the year, when the Sun reaches the celestial longitude of 270°||Shíyīyuè 5, 2017
about December 22
|The node of the solar years|
|Spring/Autumn Pray||Solar term (variable date)||The fifth Wù (戊) day after Spring/Autumn Commences||March 21
|a version of Spring/Autumn equinox|
|Opening Day (business festival)||Fixed date||01-05
|In the old days, merchants used to open their stores from Zhēngyuè 5, and host a prayer service on that day. God of Wealth's Day, which the prayer service is called God of Wealth is Welcome.|
Touya & Weiya
|First/Last Thanksgiving (business festival)||Fixed date||02-02/00-16
Èryuè 2 / Làyuè 16
|In the Ancient China, business owners hosted the Yaji rites (Chinese: 牙祭; pinyin: Yaji) at the 2nd and 16th day of each month from Eryue to Layue, to reward the local guardian god and their employees. The First/Last Thanksgiving rite is held on Èryue 2/Làyuè 16.|
Before the Zhou dynasty, the Chinese calendars used a solar calendar.
According to Ancient Chinese literature, the first version was the five-phases calendar (五行曆; 五行历), which came from the tying knots culture. In the five-phases calendar, a year was divided into five phases which were expressed by five ropes. Each rope was folded into halves, and the day in the corner was the capital day (行御). They're three sections in each halves, and the Chinese Character of phase is the pictograph of the rope of the tying knots. The ten half-ropes were arranged into a row, and a man shape was engraved by the ropes. The part of man shape derived into 10 heaven stems. The days in each sections were recorded with 12 earthly branches. So, in the five-phases calendar, a year is fives phases or ten months, and a phase is six sections or 73 days. The remainder of each phases are marked in the Hetu, which is found in Song Dynasty.
The second version is the four-seasons calendar (四時八節曆; 四时八节历). In the four-seasons calendar, the days were counting by ten, and three ten-days weeks were built into a month. There were 12 months in a year, and a week were intercalated in the hot month. In the age of four-seasons calendar, the 10 heaven stems and 12 earthly branches were used to mark days synchronously.
The third version is the balanced calendar (調曆; 调历) a year was defined into 365.25 days, and the month was defined into 29.5 days. And after each 16 months, a half-month was intercalated. There half-months were merged into months later, and the archetype of the Chinese calendar was brought out in the Spring and Autumn ages.
Oracle bone records indicate that the calendar of Shang Dynasty were a balanced calendar, and the 12, 13, even 14 months were packed into a year roughly. Generally, the month after the winter solstice was Zhēngyuè.
In Zhou dynasty, the authority issued the official calendar, which is a primitive lunisolar calendar. The year beginning of Zhou's calendar (周曆; 周历) is the day with dark moon before the winter solstice, and the epoch is the Winter Solstice of a Dīngyǒu year.
Some remote vassal states issued their own calendars upon the rule of Zhou's calendar, such as:
These six calendars are called as the six ancient calendars (古六曆; 古六历), and are the quarter remainder calendars (四分曆; 四分历; sìfēnlì). The months of these calendars begin on the day with the darkmoon, and there are 12 or 13 month within a year. The intercalary month is placed at the end of the year, and called as 13th month.
The modern version of the Zhuanxu's calendar is the Chinese Qiang calendar and Chinese Dai calendar, which are the calendar of mountain peoples.
After Qin Shi Huang unified China under the Qin dynasty in 221 BCE, Qin's calendar (秦曆; 秦历) was promulgated. The Qin's calendar follows the rules of Zhuanxu's calendar, but the month order follows the Xia calendar. The months in the year are from the 10th month to the 9th month, and the intercalary month is called as the second Jiuyue (後九月; 后九月). In the early Han dynasty, the Qin calendar continued to be used.
Emperor Wu of the Han dynasty introduced reforms halfway through his administration. His Taichu or Grand Inception Calendar (太初曆; 太初历) introduced 24 solar terms which determined the month names. The solar year was defined as 365 385/1539 days, and divided into 24 solar terms. Each couples of solar terms are associated into 12 climate terms. The lunar month was defined as 29 43/81 days and named according to the closest climate term. The mid-climate in the month decides the month name, and a month without mid-climate is an intercalary month.
The Taichu calendar established the frame of the Chinese calendar, Ever since then, there have been over 100 official calendars in Chinese which are consecutive and follow the structure of Tàichū calendar both. There're several innovation in calendar calculation in the history of over 2100 years, such as:
The Chinese calendar lost the status of the official statutory calendar in China at the beginning of the 20th century, but its use has continued for various purposes.
In 1928 the Republic of China adopted the UTC+8 timezone, instead of Beijing Mean Solar Time, and so Chinese calendars produced in mainland China switched to using UTC+8 in the following year. However, the switch in time standard used in Chinese calendars has not been universally adopted in areas such as Taiwan and Hong Kong, and some calendars still followed the last calendar of the Qing dynasty that was published in 1908. In 1978, this practice caused confusion regarding the date of the Mid-autumn festival, and as a result those areas switched to the UTC+8-based Chinese calendar thereafter.
In the late Ming dynasty, Xu Guangqi and his colleagues worked out the new calendar based on Western astronomical arithmetic. But the new calendar was not released before the end of the Ming dynasty. In the early Qing dynasty, Johann Adam Schall von Bell submitted the calendar to the Shunzhi Emperor. The Qing government released the calendar under the name the Shíxiàn calendar, which means seasonal charter. In the Shíxiàn calendar, the solar terms each correspond to 15° along the ecliptic. It meant the Chinese calendar can be used as astronomical calendar. However, the length of the climate term near the perihelion is shorter than 30 days and there may be two mid-climate terms. The rule of the mid-climate terms decides the months, which is used for thousands years, lose its validity. The Shíxiàn calendar changed the rule to "decides the month in sequence, except the intercalary month."
The version of the traditional Chinese calendar currently being used follows the rules of the Shíxiàn calendar, except that:
To optimize the Chinese calendar, astronomers have released many proposed changes. A typical proposal was released by Gao Pingzi (高平子; 1888-1970), a Chinese astronomer who was one of the founders of Purple Mountain Observatory. In his proposal, the month numbers are calculated before the dark moons and the solar terms were rounded to the day. Under his proposal, the month numbers are the same for the Chinese calendar upon different time zones.
As the intercalary month is determined by the first month without mid-climate and the exact time when each mid-climate happen would vary according to time zone, countries that have adopted the calendar but calculate with their own time could vary from the one used in China because of this. For instance, the 2012 FTG happened in UTC May 20 15:15, which would translate to May 20 23:15 in UTC+8, making FTG the mid-climate for the fourth month of that traditional Chinese year [April 21 ~ May 20 in Gregorian calendar], but in Korea it happened in May 21 00:15 in UTC+9, and as new moon take place in May 21 in that month, therefore the month before that would only consist of the SC solar term, lacking mid-climate. As a result, the month starting at April 21 would be an intercalary month in Korean calendar, but not in Chinese Calendar, and the intercalary month in Chinese calendar would start in the month after, in the fifth month starting from May 21, which would only consist of the solar term STG, while the month in Korean Calendar would have both FTG and STG solar term in it.
Among the ethnic groups inhabiting the mountains and plateaus of southwestern China, and those living in the grasslands of northern China, their civil calendars show a diversity of practice based upon their characteristic phenology and culture, but they are based on the algorithm of the Chinese calendar of different periods, especially those of the Tang dynasty and pre-Qin dynasty period.