Inches to CM converter
1 in = 2.54 cm
Multiply by 2.54 and you have the exact answer: 12 in is 30.48 cm, not "about 30". Handy for TV diagonals, bike frames and clothing measurements.
12 in = 30.48 cm
Formula: cm = in × 2.54
12 in in every length unit
- millimetre
- centimetre
- metre
- kilometre
- foot
- yard
- mile
- nautical mile
How to convert inches to centimetres
cm = in × 2.54
Example: 12 in × 2.54 = 30.48 cm.
inch: 1 in = 2.54 cm exactly (NIST SP 811, App. B (1959 yard & pound agreement))
centimetre: 1 cm = 0.01 m (BIPM SI Brochure)
Going the other way? Use the cm to inches converter.
Where the number 2.54 comes from
Nothing is measured here. Every step below is a definition written into law or into the SI.
1 in
Inches to CM table
| inches (in) | centimetres (cm) |
|---|---|
| 0.25 | 0.635 |
| 0.5 | 1.27 |
| 0.75 | 1.905 |
| 1 | 2.54 |
| 2 | 5.08 |
| 3 | 7.62 |
| 4 | 10.16 |
| 5 | 12.7 |
| 6 | 15.24 |
| 7 | 17.78 |
| 8 | 20.32 |
| 9 | 22.86 |
| 10 | 25.4 |
| 11 | 27.94 |
| 12 | 30.48 |
| 13 | 33.02 |
| 14 | 35.56 |
| 15 | 38.1 |
| 16 | 40.64 |
| 17 | 43.18 |
| 18 | 45.72 |
| 19 | 48.26 |
| 20 | 50.8 |
| 21 | 53.34 |
| 22 | 55.88 |
| 23 | 58.42 |
| 24 | 60.96 |
| 30 | 76.2 |
| 36 | 91.44 |
| 48 | 121.92 |
| 60 | 152.4 |
| 72 | 182.88 |
Questions
How many centimetres are in 1 inch?
1 in = 2.54 cm.
What is the formula to convert inches to centimetres?
cm = in × 2.54. 1 in = 2.54 cm exactly; 1 cm = 0.01 m.
Is this conversion exact?
Yes. Both units are defined exactly (NIST SP 811, App. B (1959 yard & pound agreement); BIPM SI Brochure), so the factor is exact and results are only rounded for display.
What is 12 in in cm?
12 in = 30.48 cm.