How to convert millimetres to centimetres
One millimetre equals 0.1 centimetres, so multiply the number of millimetres by 0.1:
cm = mm × 0.1
mm = cm ÷ 0.1 (1 cm = 10 mm)
Example: 10 mm → 10 × 0.1 = 1 cm.
Going the other way, divide by 0.1, or multiply by 10; the centimetres to millimetres converter does it for you.
Everyday values
| Millimetres | Centimetres | For example |
|---|---|---|
| 1 mm | 0.1 cm | about the thickness of a credit card (0.76 mm) |
| 10 mm | 1 cm | one centimetre |
| 25.4 mm | 2.54 cm | one inch |
| 50 mm | 5 cm | 5 cm |
| 100 mm | 10 cm | 10 cm |
When you need this conversion
Ten millimetres make one centimetre, so just move the decimal point one place to the left: 85 mm = 8.5 cm. Technical drawings use millimetres, while everyday measurements often use centimetres.
Millimetre to centimetre conversion table
| mm | cm | mm | cm |
|---|---|---|---|
| 5 mm | 0.5 cm | 65 mm | 6.5 cm |
| 10 mm | 1 cm | 70 mm | 7 cm |
| 15 mm | 1.5 cm | 75 mm | 7.5 cm |
| 20 mm | 2 cm | 80 mm | 8 cm |
| 25 mm | 2.5 cm | 85 mm | 8.5 cm |
| 30 mm | 3 cm | 90 mm | 9 cm |
| 35 mm | 3.5 cm | 95 mm | 9.5 cm |
| 40 mm | 4 cm | 100 mm | 10 cm |
| 45 mm | 4.5 cm | 105 mm | 10.5 cm |
| 50 mm | 5 cm | 110 mm | 11 cm |
| 55 mm | 5.5 cm | 115 mm | 11.5 cm |
| 60 mm | 6 cm | 120 mm | 12 cm |
About the units
- Millimetre (mm): one thousandth of a metre.
- Centimetre (cm): one hundredth of a metre.
Both are units of length. The conversion factor comes from the exact definitions above, so the calculator is exact; results are only rounded for display (up to six significant digits).
Frequently asked questions
How many centimetres are in one millimetre?
One millimetre is 0.1 centimetres. One centimetre is 10 millimetres.
How do I convert millimetres to centimetres?
Multiply the value in millimetres by 0.1. To go back, divide by 0.1.
What is 10 mm in centimetres?
10 mm = 1 cm.
What is 25.4 mm in centimetres?
25.4 mm = 2.54 cm.
Sources
- NIST Special Publication 811 (2008), Guide for the Use of the International System of Units (SI), Appendix B: conversion factors.
- NIST Handbook 44 (2024), Appendix C: General tables of units of measurement.
Last reviewed 5 October 2026. Results are estimates; see our disclaimer.