Cun (Chinese) to Millimeters (cun to mm)

1 cun (Chinese) equals 33.33333333 millimeters (rounded).

1 cun (Chinese) = 33.33333333 millimeters

How to convert cun (Chinese) to millimeters

To convert cun (Chinese) to millimeters, multiply the number of cun (Chinese) by 33.33333333. The factor is rounded to 10 significant digits. To go the other way, multiply millimeters by 0.03.

millimeters = cun (Chinese) × 33.33333333

Example: 10 cun (Chinese) = 333.3333333 millimeters.

About these units

Cun (Chinese) (cun)

ChineseTraditional unit (still used in some regions)

The Chinese inch, 1/30 m (about 3.33 cm) in the modern market system. Also used in acupuncture, where a 'body cun' is proportional to the patient.

Hand anatomy gave the cun its role. The traditional definition is the width of a person's thumb at the knuckle, and the unit is commonly translated as the Chinese inch. That human scale is the reason acupuncture still uses a body cun, which is proportional to the patient and is not a fixed number of millimeters. Two forefingers side by side are counted as 1.5 cun, and four fingers together as 3 cun.

As a measure of ordinary objects, the cun is one tenth of a chi and ten times a fen. Under the modern market system it equals 10/3 centimeters, roughly 3.33 cm. Hong Kong kept a British-influenced standard in which the cun is about 3.715 cm, and Japan's related sun is about 3.03 cm, so the same character covers several different sizes in different places. The phrase chi cun, literally foot and inch, also became the everyday Chinese word for dimensions.

1 cun (Chinese) = 0.03333333333 meters (approximately).

Sources: Wikipedia: Cun (unit); Wikipedia: Chi (unit)

Millimeter (mm)

Metric (SI)Current unit

One thousandth of a meter. Used in engineering, manufacturing and rainfall measurement.

Carl Friedrich Gauss put the millimeter at the base of his 1832 proposal for absolute units, pairing it with the milligram and the second, although the centimeter-based CGS system later won out among scientists. The name combines the metric prefix milli-, from the Latin for one thousand, with the meter. Since 1983 a millimeter has been tied to the speed of light: it is the distance light covers in 1/299,792,458,000 of a second.

Millimeters are the language of fine mechanical work. Standard rulers are divided into them, digital calipers commonly read to 0.01 mm, and mechanical pencil leads come in 0.5 and 0.7 mm. Copy paper is about 0.1 mm thick, and a thin hair, at 0.02 to 0.04 mm across, is close to the smallest thing the naked eye can see. A wave with a frequency of 300 GHz has a wavelength of 1 mm. An inch is exactly 25.4 mm. One trap for readers in the United States is that mil there traditionally means a thousandth of an inch, not a millimeter.

1 millimeter = 0.001 meters (exactly).

Sources: Wikipedia: Millimetre; Wikipedia: Centimetre-gram-second system of units; NIST Guide to the SI, Appendix B.8: conversion factors

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