Convert mm to cm
Convert mm to cm instantly. 1 mm = 0.1 cm. Formula, worked examples and a quick reference table.
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One millimeter equals 0.1 centimeters. To convert any number of millimeters to centimeters, multiply by 0.1.
The converter above works in both directions and updates as you type. Below you will find the formula, a worked example and a reference table of common values.
Length conversions come up wherever a measurement crosses a border: a height given in feet and inches on a form that wants centimetres, a running distance recorded in kilometres and compared against miles, a component specified in millimetres and ordered from a supplier working in inches. The conversions themselves are exact — the inch, foot, yard and mile have all been defined in metric terms since 1959 — so any discrepancy comes from rounding, not from the units disagreeing.
mm to cm formula
To go the other way, use millimeter = centimeter ÷ 0.1.
About these units
The millimetre is the working unit of engineering drawings and machining across most of the world, precise enough that dimensions rarely need decimals.
The centimetre is a hundredth of a metre. It is the everyday unit for body height and clothing sizes almost everywhere outside the United States, where feet and inches persist.
Millimeter is also written millimetre, millimetres and millimeters. Centimeter is also written centimetre, centimetres and centimeters.
Sources
mm to cm conversion table
| Millimeter | Centimeter |
|---|---|
| 1 mm | 0.1 cm |
| 2 mm | 0.2 cm |
| 3 mm | 0.3 cm |
| 5 mm | 0.5 cm |
| 10 mm | 1 cm |
| 20 mm | 2 cm |
| 25 mm | 2.5 cm |
| 50 mm | 5 cm |
| 100 mm | 10 cm |
| 250 mm | 25 cm |
| 500 mm | 50 cm |
| 1,000 mm | 100 cm |
Frequently asked questions
How many centimeters are in a millimeter? +
There are 0.1 centimeters in one millimeter.
What is 10 mm in cm? +
10 mm equals 1 cm. Multiply 10 by 0.1.
How do I convert centimeter back to millimeter? +
Use millimeter = centimeter ÷ 0.1. The converter above handles both directions, or see our dedicated cm to mm page.
How accurate is this millimeter to centimeter conversion? +
The factor used is 0.1, carried at full double precision. Where a unit has an exact legal definition the factor is exact rather than approximate. Rounding is applied only to the displayed result, so the answer is never a calculation done on an already-rounded number.
Is there a quick way to estimate mm to cm in my head? +
Divide by 10. That matches the true factor of 0.1 exactly, so no adjustment is needed for a mental estimate.