Millimeters to Centimeters
An instant millimeters-to-centimeters converter, with the formula and a reference table below.
| Millimeters | Centimeters |
|---|---|
| 1 mm | 0.1 cm |
| 2 mm | 0.2 cm |
| 3 mm | 0.3 cm |
| 5 mm | 0.5 cm |
| 10 mm | 1 cm |
| 25 mm | 2.5 cm |
| 50 mm | 5 cm |
| 100 mm | 10 cm |
How to use
- Enter a value in the Millimeters field.
- The Centimeters figure appears immediately — no button to press.
- Typing in the Centimeters field converts back to Millimeters the same way.
- Use the reference table for the values that come up most often.
Millimeters to Centimeters formula
Converting millimeters to centimeters is a single multiplication by 0.1.
cm = mm × 0.1
Put another way, one millimeter is exactly 1/10 of a centimeter.
Why this factor: the millimeter and the centimeter are both defined against the meter, so dividing one definition by the other gives 0.1 directly. Both definitions are set out in full below.
To go the other way, divide by 0.1 — or use the Centimeters to Millimeters converter, which is the same calculation reversed.
Worked example
Take 100 mm and multiply by the factor 0.1: the result is 10 cm.
100 mm × 0.1 = 10 cm
The converter above does this for any value you type, in either direction.
What is a millimeter?
A millimeter is one thousandth of a meter — the working precision unit of manufacturing and construction.
Definition: Exactly 0.001 meter by SI prefix definition.
Where it is used: Engineering drawings, machining tolerances, timber and steel dimensions, rainfall totals.
What is a centimeter?
A centimeter is one hundredth of a meter, the everyday metric unit for body and object measurements.
Definition: Exactly 0.01 meter by SI prefix definition.
Where it is used: Height, clothing sizes, rainfall, paper and screen dimensions across the metric world.
Millimeters vs Centimeters
The millimeter and the centimeter belong to the same family of units, so converting between them is usually a matter of shifting a decimal point or applying a small whole-number factor.
Frequently asked questions
How many centimeters are in a millimeter?
One millimeter equals 0.1 centimeters.
What is the formula to convert millimeters to centimeters?
Multiply the number of millimeters by 0.1. To reverse it, divide by 0.1 instead.
How do I convert centimeters back to millimeters?
Divide by 0.1, which is the same as multiplying by 10.
How many centimeters are in 10 millimeters?
10 mm works out to 1 cm.
How is the millimeter defined?
Exactly 0.001 meter by SI prefix definition.