Length Converter
Millimeter
Definition: A millimeter (symbol: mm) is a unit of length in the International System of Units (SI). It is defined as 1/1000 of a meter.
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.
Current use: Millimeters are used to measure very small distances and lengths, often in engineering, manufacturing, and hardware specifications.
Inch
Definition: An inch (symbol: in) is a unit of length in the imperial and US customary systems. It was defined in 1959 to be exactly 25.4 millimeters.
History/origin: Derived from the Latin unit "uncia" which meant "one-twelfth" (of a Roman foot). Historically, it was also defined as the length of three dry barleycorns laid end-to-end.
Current use: The inch is mostly used in the United States, Canada, and the United Kingdom. It is also the global standard for measuring screen sizes (phones, TVs) and pipe diameters.
Millimeter to Inch Conversion Table
| Millimeter [mm] | Inch [in] |
|---|---|
| 0.01 mm | 0.0003937 in |
| 0.1 mm | 0.00393701 in |
| 1 mm | 0.03937008 in |
| 2 mm | 0.07874016 in |
| 3 mm | 0.11811024 in |
| 5 mm | 0.19685039 in |
| 10 mm | 0.39370079 in |
| 20 mm | 0.78740157 in |
| 50 mm | 1.96850394 in |
| 100 mm | 3.93700787 in |
| 1000 mm | 39.37007874 in |
How to Convert Millimeter to Inch
1 mm = 0.03937008 in
1 in = 25.4 mm
Example: convert 15 mm to in:
15 mm = 15 × 0.03937008 in = 0.59055118 in
Did You Know?
- A millimeter is so small that a single sheet of standard paper is about 0.1 millimeters thick.
- The word "inch" comes from the Latin word "uncia," meaning one-twelfth. Historically, an inch was the width of a human thumb!