How to convert inches to centimeters
Multiply the length in inches by 2.54. One inch is exactly 2.54 centimeters, so 12 in × 2.54 = 30.48 cm and 8.5 in × 2.54 = 21.59 cm. To get millimeters, multiply by 25.4 instead; 3 in is 76.2 mm.
The converter above updates as you type and also shows the result in millimeters, meters and feet and inches. Use the ⇄ button to switch to cm to inches.
Inches to centimeters chart
| Inches | Centimeters | Millimeters |
|---|---|---|
| 0.25 in | 0.64 cm | 6.3 mm |
| 0.5 in | 1.27 cm | 12.7 mm |
| 1 in | 2.54 cm | 25.4 mm |
| 2 in | 5.08 cm | 50.8 mm |
| 3 in | 7.62 cm | 76.2 mm |
| 4 in | 10.16 cm | 101.6 mm |
| 5 in | 12.7 cm | 127 mm |
| 6 in | 15.24 cm | 152.4 mm |
| 8 in | 20.32 cm | 203.2 mm |
| 10 in | 25.4 cm | 254 mm |
| 12 in | 30.48 cm | 304.8 mm |
| 15 in | 38.1 cm | 381 mm |
| 24 in | 60.96 cm | 609.6 mm |
| 30 in | 76.2 cm | 762 mm |
| 36 in | 91.44 cm | 914.4 mm |
| 48 in | 121.92 cm | 1,219.2 mm |
| 60 in | 152.4 cm | 1,524 mm |
| 72 in | 182.88 cm | 1,828.8 mm |
Where you will use this conversion
- US TV, monitor and phone screen sizes compared with metric listings
- Paper sizes: US Letter is 8.5 × 11 in, which is 21.59 × 27.94 cm
- Picture frames, prints and posters
- Lumber, hardware and fastener dimensions
- Shopping from US stores when you think in centimeters
Good to know
A handy rule of thumb is that 4 inches is about 10 centimeters (the exact value is 10.16 cm). The common A4 sheet is 21 × 29.7 cm, slightly narrower and taller than US Letter, which is why documents sometimes shift when printed in another country. Because the inch is defined as exactly 2.54 cm, this conversion has no rounding error beyond the digits shown.
Frequently asked questions
How many centimeters are in an inch?
There are exactly 2.54 centimeters in one inch. To convert inches to centimeters, multiply by 2.54.
How do I convert inches to millimeters?
Multiply the inches by 25.4. For example, 3 inches is 76.2 mm and 0.5 inches is 12.7 mm.
How tall is 70 inches in cm?
70 inches is 177.8 cm, which is 5 ft 10 in.
How do I convert feet and inches to centimeters?
Convert everything to inches (feet × 12 + inches), then multiply by 2.54. For example, 5 ft 9 in is 69 inches, which is 175.26 cm.