There are 2.54 centimeters in an inch
There are 2.54 centimeters in an inch. The working, a reference table and answers to the related "how many" questions people actually ask.
The working
1 in = 2.54 cm
1 in × 2.54 = 2.54 cm
Why this figure matters
Fixed by international agreement in 1959 — every inch, in every English-speaking country since, is exactly 2.54 cm.
Inches to centimeters
| Inches | Centimeters |
|---|---|
| 1 inch | 2.54 centimeters |
| 2 inches | 5.08 centimeters |
| 5 inches | 12.7 centimeters |
| 10 inches | 25.4 centimeters |
| 12 inches | 30.48 centimeters |
Questions people ask
How many centimeters are in an inch?
There are 2.54 centimeters in an inch.
Where does the 2.54 figure come from?
1 in = 2.54 cm
How many inches is 15 centimeters?
15 Centimeters is 5.905511811 inches.
How many inches is 18 centimeters?
18 Centimeters is 7.086614173 inches.
How many inches is 25 centimeters?
25 Centimeters is 9.842519685 inches.
How many inches is 45 centimeters?
45 Centimeters is 17.71653543 inches.
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Last updated 26 August 2026