Centimeters to Millimeters
Centimeters to millimeters: 1 cm = 10 mm. Formula, a 12-row reference table, worked examples and the reverse conversion.
Did this tool work for you?
The cm to mm formula
Going from centimeters to millimeters means scaling the number by 10. A quantity of 1 cm therefore shows up as 10 mm in the widget above.
Because the relationship is a plain ratio, doubling the centimeters doubles the millimeters, and 0 cm stays 0 mm. The inverse ratio is 0.1, meaning 1 mm = 0.1 cm.
Centimeters and their value in millimeters
Here are 12 values converted from centimeters to millimeters. Each row is the left-hand number multiplied by 10.
| Centimeters (cm) | Millimeters (mm) |
|---|---|
| 0.5 | 5 |
| 1 | 10 |
| 2 | 20 |
| 5 | 50 |
| 10 | 100 |
| 20 | 200 |
| 25 | 250 |
| 50 | 500 |
| 100 | 1,000 |
| 250 | 2,500 |
| 500 | 5,000 |
| 1,000 | 10,000 |
These figures are generated, not typed in by hand, and follow the widget's rounding rules described in the questions further down.
Three sample conversions from centimeters to millimeters
For the first example, take 1.5 centimeters. The factor is 10, so the amount comes to 15 millimeters.
Next, 42 cm: the converter shows 420 mm. Because the ratio is fixed, the mm figure is 10 times the cm figure.
Finally, convert 350 millimeters to centimeters: dividing by 10 gives 35.
Converting millimeters back to centimeters
The mirror-image page is Millimeters to Centimeters, where 1 mm = 0.1 cm. Its table and examples use millimeters as the starting unit.
The full Length Converter lets you choose any two units from the same list, not only cm and mm.
Related conversions for centimeters and millimeters
Other pairs that use the same unit table are listed here.
Frequently asked questions
What is 1 cm in mm?
1 cm = 10 mm in the converter's unit table. Multiplying by 10 gives 100 mm; multiplying by 100 gives 1,000 mm.
How many cm make up 1 mm?
Each millimeter corresponds to 0.1 centimeters; scaled up by 10, that is 1 cm.
What is 7.5 centimeters in millimeters?
Using 10 as the multiplier, 7.5 centimeters equals 75 millimeters.
How many decimal places does the cm to mm converter show?
Rounding happens only when a result is displayed. Between 1 and 1,000 the display has 10 significant digits, under 1 it has 8, and from 1,000 up it allows 6 decimals with comma separators; very large or very small results switch to scientific notation. Entering 0.123456789 cm shows 1.23456789 mm, and 1,234.5678 cm shows 12,345.678 mm.
Which formula does the cm-to-mm converter use?
Conversion goes through a shared reference unit: cm is scaled into it, and the result is scaled out into mm. The two steps combine into one multiplication by 10.
How do I turn millimeters into centimeters?
The page titled "Millimeters to Centimeters" covers it, or you can press the swap button in the widget above. In the reverse direction multiply by 0.1, or equivalently divide by 10, giving 2.5 cm for an input of 25 mm.
Learn more from an authoritative source:
NISTInches to Feet Converter
Convert inches to feet instantly. See the result in feet and inches combined (e.g. 5'4"), decimal feet, and centimetres.
Weight & Mass Converter
Convert between kilograms, pounds, ounces, grams, stones, tonnes, and more weight units.
Temperature Converter
Convert between Celsius, Fahrenheit, Kelvin, and Rankine instantly.
Volume Converter
Convert between litres, millilitres, gallons, cups, fluid ounces, cubic metres, and more.
Area Converter
Convert between square metres, square feet, acres, hectares, square kilometres, and more.
Speed Converter
Convert between km/h, mph, m/s, knots, and Mach number instantly.
Results are estimates for informational purposes only and do not constitute professional financial, medical, legal, or technical advice. Read full disclaimer →