Centimeters to millimeters

Type a value in centimeters to see it in millimeters straight away, or type in the second box to convert back.

Loading the tool…

Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.

How to use it

  1. Type the value in the centimeters box.
  2. Read the result in millimeters as you type, and pick the precision you need.
  3. Swap the direction to convert back, or copy the result.

How it is calculated

mm = cm × 10

Multiply the value in centimeters by 10 to get millimeters.

Example

To convert 25 cm to millimeters: 25 × 10 = 250 mm.

Conversion table

Centimeters (cm)Millimeters (mm)
110
220
330
550
10100
20200
25250
50500
1001,000
2502,500
5005,000
1,00010,000

About the units

Centimeter
A centimeter is one hundredth of a meter, used for everyday sizes such as height and clothing.
Millimeter
A millimeter is one thousandth of a meter, common in engineering drawings and thickness measurements.

Limits and caveats

  • Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
  • Both unit factors are exact by their official definitions.

Questions about this tool

How many millimeters are in one centimeter?

1 cm = 10 mm exactly.

How do I convert centimeters to millimeters?

Use mm = cm × 10. For example, 25 cm = 250 mm.

How many centimeters are in one millimeter?

1 mm = 0.1 cm.

Are the inch, foot and mile factors exact or rounded?

They are exact by definition. Since the 1959 agreement one inch is exactly 2.54 cm, one foot 0.3048 m and one mile 1609.344 m.

What is the difference between a mile and a nautical mile?

A statute mile is 1609.344 meters and is used on roads. A nautical mile is 1852 meters and is used at sea and in aviation.