# Centimeters to Millimeters (cm to mm)

Source: https://www.unitconvertercalculator.com/length/centimeters-to-millimeters/

**1 cm = 10 mm**

One centimeter equals exactly 10 millimeters. This is the simplest and most frequently used metric conversion in everyday life. Moving from centimeters to millimeters just shifts the decimal one place right. Both units appear on every metric ruler.

## Formula

Convert Centimeters to Millimeters

## Conversion Table

| Centimeters (cm) | Millimeters (mm) |
|---|---|
| 0.1 cm | 1 mm |
| 0.5 cm | 5 mm |
| 1 cm | 10 mm |
| 2 cm | 20 mm |
| 3 cm | 30 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 |
| 50 cm | 500 mm |
| 100 cm | 1000 mm |
| 200 cm | 2000 mm |
| 500 cm | 5000 mm |
| 1000 cm | 10000 mm |

## Units

### Centimeter (cm)

A metric unit of length equal to one hundredth of a meter. Commonly used for body height, clothing sizes, and everyday measurements.

### Millimeter (mm)

A metric unit of length equal to one thousandth of a meter. Used in engineering, manufacturing, and precise measurements.

## Background

A 30 cm ruler shows 300 mm. A credit card at 8.56 cm is 85.6 mm. A human hair at 0.0075 cm is 0.075 mm (75 micrometers). In engineering drawings, millimeters are standard because they avoid decimal points for common dimensions. A 2.5 cm bolt is simply a 25 mm bolt.

## Good to Know

Every metric ruler has both cm and mm markings. Children learn centimeters first. Engineers learn to think in millimeters. The transition from cm-thinker to mm-thinker is one of the subtle signs of technical training.

## FAQ

### How many millimeters are in 1 centimeter?

One centimeter contains exactly 10 millimeters. This is the defining 'centi to milli' metric relationship.

### How do I convert cm to mm?

Multiply by 10 or move the decimal point one place right. For example, 3.5 cm = 35 mm.

### When do I use mm instead of cm?

Engineering and manufacturing prefer millimeters because most part dimensions are whole numbers in mm. A 25 mm bolt is cleaner than 2.5 cm. Medicine also uses mm for small measurements like tumor sizes.

## Non-Frequently Asked Questions

### Why do we need both centimeters and millimeters?

For the same reason you need both dollars and dimes. Centimeters give round numbers for everyday objects (a phone is 15 cm). Millimeters give round numbers for precision work (a screw is 8 mm). Using the wrong one is like paying for coffee in pennies.

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## See Also

- [Millimeters to Centimeters](https://www.unitconvertercalculator.com/length/millimeters-to-centimeters/)