# Convert mm to m

Please provide values below to convert millimeter [mm] to meter [m], or *vice versa*.

### 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 the current definition, the meter was based on the length of a prototype meter bar. As with all SI units, the definition of the meter is subject to change, and it is possible that a new definition of the meter will be in place in the future.

### Meter

**Definition:** A meter, or metre (symbol: m), is the base unit of length and distance in the International System of Units (SI). Currently, the meter is defined as the distance traveled by light in 1/299 792 458 of a second.

**History/origin:** Originally, in 1793, the meter was defined as one ten-millionth of the distance from the equator to the North Pole. This changed in 1889, when the International prototype metre was established as the length of a prototype meter bar (made of an alloy of 90% platinum and 10% iridium) measured at the melting point of ice. In 1960, the meter was again redefined, this time in terms of a certain number of wavelengths of a certain emission line of krypton-86. The current definition of the meter was adopted in 1983.

**Current use:** Being the SI unit of length, the meter is used worldwide in many applications such as measuring distance, height, length, width, etc. The United States is one notable exception in that it largely uses US customary units such as yards, inches, feet, and miles instead of meters in everyday use.

**Possible future changes:** The definition of some SI base units may change in the near future. The International Committee for Weights and Measures (CIPM) has proposed re-definition of some of the SI base units in an attempt to further improve the system. Although the definitions of some units may change, the actual size of the units would remain the same; the change in definition will not have much (if any) effect on the daily use of these units.

The meter is one of the units that is being considered for another re-definition. Currently it is based on the length of the path travelled by light in a vacuum during a specific time interval, noted above. If changed, the new definition of the meter will be based on defining the fixed numerical value of the speed of light in vacuum as 299,799,458, expressed in units of m·s^{-1}, where the second is defined in terms of cesium frequency.

### Millimeter to Meter Conversion Table

Millimeter [mm] | Meter [m] |
---|---|

0.01 mm | 1.0E-5 m |

0.1 mm | 0.0001 m |

1 mm | 0.001 m |

2 mm | 0.002 m |

3 mm | 0.003 m |

5 mm | 0.005 m |

10 mm | 0.01 m |

20 mm | 0.02 m |

50 mm | 0.05 m |

100 mm | 0.1 m |

1000 mm | 1 m |

### How to Convert Millimeter to Meter

1 mm = 0.001 m

1 m = 1000 mm

**Example:** convert 15 mm to m:

15 mm = 15 × 0.001 m = 0.015 m