Convert Centimeters to Millimeters
1 centimeter (cm) equals 10 millimeters (mm).
1 cm = 10 mm
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk centimeter to millimeter converter to paste a column from Excel.
How to Convert Centimeter to Millimeter
- 1 cm = 10 mm
- 1 mm = 0.1 cm
- Example: convert 15 cm to mm: 15 cm = 15 × 10 mm = 150 mm
Formula
mm = cm × 10
Derivation from SI units:
- 1 cm = 10⁻² m
- 1 mm = 10⁻³ m
- 1 cm = 0.01 m ÷ 0.001 m per mm = 10 mm
Both units are defined exactly, so the factor is exact. Centimeter definition: centimeter; Millimeter definition: millimeter.
Worked examples
- A 2.5 cm screw is 25 mm long.
2.5 cm × 10 = 25 mm - 0.5 cm is 5 mm.
0.5 cm × 10 = 5 mm
Centimeter to Millimeter conversion table
| Centimeters (cm) | Millimeters (mm) |
|---|---|
| 1 cm | 10 mm |
| 2 cm | 20 mm |
| 2.54 cm | 25.4 mm |
| 5 cm | 50 mm |
| 10 cm | 100 mm |
| 15 cm | 150 mm |
| 20 cm | 200 mm |
| 25 cm | 250 mm |
| 30 cm | 300 mm |
| 45 cm | 450 mm |
| 50 cm | 500 mm |
| 60 cm | 600 mm |
| 75 cm | 750 mm |
| 90 cm | 900 mm |
| 100 cm | 1000 mm |
| 120 cm | 1200 mm |
| 150 cm | 1500 mm |
| 160 cm | 1600 mm |
| 165 cm | 1650 mm |
| 170 cm | 1700 mm |
| 175 cm | 1750 mm |
| 180 cm | 1800 mm |
| 185 cm | 1850 mm |
| 190 cm | 1900 mm |
| 200 cm | 2000 mm |
Where it's used
Centimetre values are converted to millimetres for engineering drawings, which use mm by convention. Multiply by 10.
Centimeter to other length units
| Conversion | 1 cm equals |
|---|---|
| centimeter to meter | 0.01 m |
| centimeter to kilometer | 0.00001 km |
| centimeter to millimeter | 10 mm |
| centimeter to micrometer | 10000 µm |
| centimeter to nanometer | 10000000 nm |
| centimeter to angstrom | 100000000 Å |
| centimeter to mile | 0.000006213711922 mi |
| centimeter to yard | 0.01093613298 yd |
| centimeter to foot | 0.03280839895 ft |
| centimeter to inch | 0.3937007874 in |
| centimeter to mil | 393.7007874 mil |
| centimeter to nautical mile | 0.000005399568035 nmi |
Frequently asked questions
How do I convert cm to mm?
Multiply by 10: 7.5 cm = 75 mm.
How many millimeters are in 1 centimeter?
1 cm = 10 mm.
How do I convert centimeters to millimeters?
Multiply the value in cm by 10. For example, 15 cm × 10 = 150 mm.
Is the cm to mm conversion exact?
Yes. Both units are defined exactly, and 1 cm is exactly 10 mm.
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Centimeters to Millimeters. Retrieved October 17, 2026, from https://scientificconverters.com/length/centimeters-to-millimeters/
IEEE
Scientific Converters, "Convert Centimeters to Millimeters," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/length/centimeters-to-millimeters/