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Convert Centimeter to Millimeter

Please provide values below to convert centimeter [cm] to millimeter [mm], or vice versa.

Centimeter

Definition: A centimeter (symbol: cm) is a unit of length in the International System of Units (SI), the current form of the metric system. It is defined as 1/100 meters.

History/origin: A centimeter is based on the SI unit meter, and as the prefix "centi" indicates, is equal to one hundredth of a meter. Metric prefixes range from factors of 10^-18 to 10¹⁸ based on a decimal system, with the base (in this case the meter) having no prefix and having a factor of 1. Learning some of the more commonly used metric prefixes, such as kilo-, mega-, giga-, tera-, centi-, milli-, micro-, and nano-, can be helpful for quickly navigating metric units.

Current use: The centimeter, like the meter, is used in all sorts of applications worldwide (in countries that have undergone metrication) in instances where a smaller denomination of the meter is required. Height is commonly measured in centimeters outside of countries like the United States.

Millimeter

Definition: A millimeter (symbol: mm) is a unit of length in the International System of Units (SI). It is defined in terms of the meter, as 1/1000 of a meter, or the distance traveled by light in 1/299 792 458 000 of a second.

History/origin: The milli- prefix is one of many metric prefixes. It indicates one thousandth of the base unit, in this case the meter. The definition of the meter has changed over time, the current definition being based on the distance traveled by the speed of light in a given amount of time. The relationship between the meter and the millimeter is constant however. Prior to this definition, the meter was based on the length of a prototype meter bar. In 2019, the meter has been re-defined based on the changes made to the definition of a second.