Inches to millimeters
Convert inches (in) to millimeters (mm) instantly with our quick and accurate converter. Delivers reliable results using the exact conversion factor, with up to 12 decimal places of precision.
1 in = 25.40 mm
Formula
Convert inches to millimeters (in to mm) using the exact formula shown below.
Conversion formula: mm = in × 25.4
Scientific basis: This relationship is based on the exact defined conversion where 1 inch is defined as exactly 25.4 millimeters.
Equivalent value: 1 in = 25.4 mm
Example: 10 in = 10 × 25.4 = 254 mm
Explanation: To convert inches to millimeters, multiply the number of inches by 25.4.
Table
| Inches (in) | Millimeters (mm) |
|---|---|
| 1 in | 25.4 mm |
| 2 in | 50.8 mm |
| 3 in | 76.2 mm |
| 4 in | 101.6 mm |
| 5 in | 127 mm |
| 10 in | 254 mm |
| 25 in | 635 mm |
| 50 in | 1,270 mm |
| 75 in | 1,905 mm |
| 100 in | 2,540 mm |
| 1,000 in | 25,400 mm |
FAQ
What is inches?
An inch is a unit of length in both the imperial and US customary system, primarily used in the United States and the United Kingdom. One inch is defined as exactly 0.0254 meters.
What is millimeters?
A millimeter is a unit of length in the metric system (SI). The prefix milli (m) means one thousandth relative to the base unit, defining one millimeter as exactly 0.001 meters.
What is the abbreviation for inches?
The standard abbreviation for inches is in.
How to convert from inches to millimeters?
To convert inches to millimeters, multiply the number of inches by 25.4.
Example: 5 in × 25.4 = 127 mm
How many millimeters is there in 1 inch?
There are exactly 25.4 millimeters in 1 inch.