Chinese units of measurement, known in Chinese as the shìzhì ("market system"), are the traditional units of measurement of the Han Chinese. Although Chinese numerals have been decimal (base-10) since the Shang, several Chinese measures use hexadecimal (base-16). Local applications have varied, but the Chinese dynasties usually proclaimed standard measurements and recorded their predecessor's systems in their histories.

In the present day, the People's Republic of China maintains some customary units based upon the market units but standardized to round values in the metric system, for example the common jin or catty of exactly 500g. The Chinese name for most metric units is based on that of the closest traditional unit; when confusion might arise, the word "market" (, shì) is used to specify the traditional unit and "common" or "public" (, gōng) is used for the metric value. Taiwan, like Korea, saw its traditional units standardized to Japanese values and their conversion to a metric basis, such as the Taiwanese ping of about 3.306m2 based on the square ken. The Hong Kong SAR continues to use its traditional units, now legally defined based on a local equation with metric units. For instance, the Hong Kong catty is precisely .

The names lí ( or ) and fēn () are used for small units of length, area, and mass; however, they refer to different magnitudes.

History

According to the Liji, the legendary Yellow Emperor created the first measurement units. The Xiao Erya and the Kongzi Jiayu state that length units were derived from the human body. According to the Records of the Grand Historian, these human body units caused inconsistency, and Yu the Great, another legendary figure, unified the length measurements. Rulers with decimal units have been unearthed from Shang dynasty tombs.

In the Zhou dynasty, the king conferred nobles with powers of the state and the measurement units began to be inconsistent from state to state. After the Warring States period, Qin Shi Huang unified China, and later standardized measurement units. In the Han dynasty, these measurements were still being used, and were documented systematically in the Book of Han.

Republican Era

On 7 January 1915, the Beiyang government promulgated a measurement law to use not only metric system as the standard but also a set of Chinese-style measurement based directly on the Qing dynasty definitions ()..

On 16 February 1929, the Nationalist government adopted and promulgated The Weights and Measures Act to adopt the metric system as the official standard and to limit the newer Chinese units of measurement () to private sales and trade in Article 11, effective on 1 January 1930. These newer "market" units are based on rounded metric numbers.

These units are still retained for use in the Republic of China-controlled territories of Kinmen and Matsu nowadays.

People's Republic of China The Government of the People's Republic of China continued using the market system along with metric system, as decreed by the State Council of the People's Republic of China on 25 June 1959, but 1 catty being 500 grams, would become divided into 10 (new) taels, instead of 16 (old) taels, to be converted from province to province, while exempting Chinese prescription drugs from the conversion to prevent errors. 1959 Gazette of the State Council of the People's Republic of China, No. 180, pages 311 to 312

On 27 February 1984, the State Council of the People's Republic of China decreed the market system to remain acceptable until the end of 1990 and ordered the transition to the national legal measures by that time, but farmland measures would be exempt from this mandatory metrication until further investigation and study.Decree of the State Council Concerning the Use of Uniform Legal Measures in the Country

Hong Kong

In 1976 the Hong Kong Metrication Ordinance allowed a gradual replacement of the system in favor of the International System of Units (SI) metric system.Yearbook HK. "Yearbook." Metrication. Retrieved on 26 April 2007. The Weights and Measures Ordinance defines the metric, Imperial, and Chinese units.Cap. 68 WEIGHTS AND MEASURES ORDINANCE As of 2012, all three systems are legal for trade and are in widespread use.

Macau On 24 August 1992, Macau published Law No. 14/92/M to order that Chinese units of measurement similar to those used in Hong Kong, Imperial units, and United States customary units would be permissible for five years since the effective date of the Law, 1 January 1993, on the condition of indicating the corresponding SI values, then for three more years thereafter, Chinese, Imperial, and US units would be permissible as secondary to the SI.Law No. 14/92/M ( ; Lei n.o 14/92/M)

Ancient Chinese units

Length

Traditional units of length include the chi (), bu (), and li (). The precise length of these units, and the ratios between these units, has varied over time. 1 bu has consisted of either 5 or 6 chi, while 1 li has consisted of 300 or 360 bu.

+Length in metresSchinz, 1996Dynastychibuli= 5 chi= 6 chi= 300 bu= 360 buShang ()0.16750.83751.0050301.50361.800.16900.84501.0140304.20365.04Western Zhou (–771 BC)0.19900.99501.1940358.20429.84Eastern Zhou (–256 BC)0.22001.10001.3200396.00475.2000.22701.13501.3620408.60490.320.23101.15501.3860415.80498.96Qin (–206 BC)0.22601.13001.3560406.80Schinz, p. 476.415.80Dubs (1938), pp. 276-280; (1955), p. 160, n. 7.Hulsewé (1961), pp. 206–207.488.16Han (–9 AD; 25–220 AD) 0.23001.15001.3800414.00496.800.23811.18051.4286415.80Hill (2015), "About the Measurements", pp. xxiii-xxiv. 415.80 428.58 514.30Wei - Sui (–266 AD; 581 to 618 AD)0.25501.27501.5300459.00550.80Tang (–690 AD; 705–907 AD)0.24651.23251.4790369.75443.700.29551.47751.7730443.25531.90Song (–1279 AD)0.27001.35001.6200405.00486.00Northern Song (–1127 AD)0.30801.54001.8480462.00554.40Ming (–1644 AD)0.3008–0.31901.5040–1.59501.8048–1.9140451.20–478.50541.44–574.20Qing (–1912 AD)0.3080–0.33521.5400–1.67601.8048–2.0112462.00–503.89554.40–603.46

Mass

Ancient Chinese weight units are mostly defined around the jin or catty. Blanks in the table means that the derived unit is not used in the era.

+Mass in gramsDynastyshi/dan (石)jun (鈞)jin (斤)liang (兩)zhu (銖)qian (錢)fen (分) 120 jin 30 jin 1 jin jin jin jin jin Pre-Qin 30000 7500 250 15.625 0.651 1.56250.15625 Qin 30360 7590 253 15.8125 0.658854166667 1.58125 0.158125 Western Han 29760 7440 248 15.5 0.6458333333331.550.155 Eastern Han, Three Kingdoms, Jin 26400 6600 220 13.8 0.575 1.375 0.1375N. & S. S. Qi 330 2.0625 0.20625 Liang, Chen 26400 6600 220 13.75 0.575 1.375 0.1375 N. Wei & N. Qi 440 2.75 0.275 N. Zhou 660 4.125 0.4125 Sui Small system 26400 6600 220 13.75 0.575 1.3750.1375 Large system 79320 19830 661 41.3125 1.721354166667 4.131250.413125 Tang Song, Yuan 75960 18990 633 39.5625 1.6484375 3.95625 0.395625 Ming, Qing 70800 17700 590 36.875 1.536458333333 3.6875 0.36875

Time

For daytime and nighttime units, the following assume a standardized sundown of yǒu shí central 1 kè (19:12 in 24-hour notation). + Table of time unitsUnit nameUnit valueNotesCharacterRelativeMetric/modern miǎo fēn 144 milliseconds Defined in 1280 fēn day 14.4 second kè (minor) 1/6 major kè 144 secondsThe major kè was defined at (rarely , , or ) day during most of Chinese history. It became established at day after the Qing dynasty, becoming the same as the modern kè.(major) day 14 minutes 24 secondsshí/shíchénNachum Dershowitz, Edward M. Reingold, "Calendrical calculations", page 207 (T) (S) day 2 hours Daytime unit diǎn (T) (S) gēng 24 minutes Nighttime unit gēng day 2.4 hours Nighttime units rì / tiān (basic unit) 1 day

Volume According to Book of Han, the fundamental unit of volume was the yuè (), the volume of 1200 grains of proso millet. 100 yuè makes a gě (), and 10 gě makes a shēng (, about 0.2 L). For dry measure, the dǒu (, "ladle"), hú (), and shi or dàn (, "[basket for] a stone['s weight]") were used for larger amounts.

The amounts of grains were also used as a measure of monthly and annual salary, particularly for official posts in the imperial bureaucracy.

The volume units have evolved through the Dynasties. By the Qing Dynasty, the shēng had become very close to the metric liter.

Modern Chinese units

All "metric values" given in the tables are exact unless otherwise specified by the approximation sign '~'. Certain units are also listed at List of Chinese classifiers → Measurement units.

The units in the following tables can be grouped into a few types: Traditional-derived units for length, area, volume, and mass. On the Chinese mainland, these units were defined in three batches. The Republic of China government promulgated in 1915 a metric version of the Qing Dynasty Yingzao Chi Kuping Zhi (). The ROC government then promulgated the "market unit" () system in 1930, redefining traditional units as simple fractions of metric units. Finally, the People's Republic of China modified the "market unit" mass system to divide 1 jin into 10 instead of the traditional 16 liang for ease of calculation. In Hong Kong and Macau the mass units were defined in terms of the British pound, specifically the 1878 definition of 0.45359 kg. The volume units were inherited from the Qing dynasty units, with a small difference compared to the 1915 definition. The length units were based on the unusually large chi found in the area of Guangdong (see ). The source of the area unit is unknown, as it appears to be based on a different chi of (obtained by taking the square root of the metric value of cek3, the square-chi). Chinese names for metric units and prefixes. This includes time units.

Length

Chinese length units promulgated in 1915 + Table of Chinese length units promulgated in 1915Unit nameUnit valueNotesPinyinCharacterRelativeMetricImperialháo 32 μmlí (T) or (S)0.32 mm0.0126 infēn3.2 mm0.126 incùn32 mm1.26 inChinese inchchǐ10.32 m12.6 inChinese footbù51.6 m5.2 ftChinese pacezhàng103.2 m3.50 ydChinese yardyǐn10032 m35.0 ydlǐ1800576 m630 ydChinese mile, this li is not the small li above, which has a different character and tone

Chinese length units effective in 1930

+ Table of Chinese length units effective in 1930Unit nameUnit valueNotesPinyinCharacterRelativeMetricImperialháo  μmChinese millí (T) or (S) mm0.0131 inChinese calibrefēn mm0.1312 inChinese linecùn cm1.312 inChinese inchchǐ1 cm13.12 inChinese footzhàng10 m3.645 ydChinese yardyǐn100 m36.45 ydChinese chainlǐ1500500 m546.8 ydChinese mile, this li is not the small li above, which has a different character and tone

Metric length units The (Mainland) Chinese word for metre is mǐ; this can take the Chinese standard SI prefixes (for "kilo-", "centi-", etc.). There exists, however, a system based on renaming traditional units, rounding them up to the closest metric unit. For the centimeter and above, the name is constructed as gōng ("public", i.e. metric) followed by the traditional unit name. For example, a kilometre is popularly known as the gōnglǐ "metric lǐ". For smaller units, a different convention exists in the engineering field. The traditional unit is appropriated without adding the gōng prefix. For example, the Chinese word (T) or (S) sī is used to express 0.01 mm.

+ Table of Chinese length unitsNameValueNoteCustomaryPRC StandardMetersMetric valuePinyinCharactershū 1 μmsī (T) or (S)10 μm1959 standard name for centimillimetre, not seen in newer standards.háo (T) or (S)100 μmlí (T) or (S)1 mmgōngfēn(T) or (S)10 mmgōngcùn100 mmgōngchǐ11 mgōngzhàng1010 mgōngyǐn100100 mgōnglǐ10001000 m

The Republic of China uses the gōng-prefixed names as the standard, legal names of the corresponding units.s:zh:度量衡法 (民國43年), The ROC Measurements Law of ROC year 43 (1954).

Hong Kong and Macau length units