Length and Area
cmtomm
Convert centimetres (cm) to millimetres (mm).
Factor1 cm = 10 mm
Converter
cm
Accepts numbers or expressions, e.g. 150 + 14.7
Result
mm
Rendered to 6 significant figures.
Formula
Formula
mm = cm × 10
Multiply any value in centimetres by 10 to obtain the value in millimetres.
Worked example
Convert 1 cm to mm.
- 01Start with 1 cm.
- 02Multiply by the conversion factor: 1 × 10 = 10 mm.
Result1 cm = 10 mm
Conversion table
| cm | mm |
|---|---|
| 1 | 10 |
| 2 | 20 |
| 5 | 50 |
| 10 | 100 |
| 20 | 200 |
| 50 | 500 |
| 100 | 1000 |
| 200 | 2000 |
| 500 | 5000 |
| 1000 | 10000 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from cm to mm?
1 cm equals 10 mm. To convert, multiply the value in centimetres by 10.
How do I convert 1 cm to mm?
1 cm = 10 mm. For any value, multiply by 10.
How do I convert mm back to cm?
Divide by the same factor — or equivalently, multiply by 0.1. So 1 mm = 0.1 cm.
When would I need to convert centimetre to millimetre?
Length conversions appear in piping, layout, and mechanical drawings — particularly when reconciling imperial fittings or instrument lengths with metric plant drawings.
Is the conversion exact?
Yes. Both cm and mm are defined by exact SI relationships, so the displayed factor is exact (any rounding shown is only for display).