Convert millimeters to centimeters instantly. Enter a value below, or use the formula and reference table further down the page.
In practice
Millimetres to centimetres divides by 10, because a centimetre is ten millimetres. It is the step you need when a part is specified in millimetres but your measuring tape or ruler is marked in centimetres. A 65 mm item is 6.5 cm, and a 150 mm ruler is 15 cm. Because the two units are so close, mistakes usually come from reading the wrong scale on a ruler, where the long numbered lines are centimetres and the small lines between them are millimetres.
How to convert millimeters to centimeters
Multiply the value by 0.1.
cm = mm × 0.1Example: 10 mm = 1 cm.
Millimeters to Centimeters conversion table
| Millimeters (mm) | Centimeters (cm) |
|---|---|
| 1 mm | 0.1 cm |
| 2 mm | 0.2 cm |
| 3 mm | 0.3 cm |
| 4 mm | 0.4 cm |
| 5 mm | 0.5 cm |
| 10 mm | 1 cm |
| 15 mm | 1.5 cm |
| 20 mm | 2 cm |
| 25 mm | 2.5 cm |
| 50 mm | 5 cm |
| 100 mm | 10 cm |
Frequently asked questions
How many centimeters is 1 millimeter?
1 millimeter equals 0.1 centimeters.
What is the formula to convert mm to cm?
To convert mm to cm, multiply the value by 0.1. The full formula is: cm = mm × 0.1.
How do I convert centimeters back to millimeters?
Use the same calculator above and type your value into the centimeters field instead — it converts in both directions. Or use the reverse formula: mm = cm ÷ 0.1.
Is the mm to cm conversion exact?
The conversion factor used here (0.1) is the standard internationally defined value. Results on this page are rounded to four decimal places for readability.