inch to mm Converter - Inch to Millimeter
Inch (in) (inch) to Millimeter (mm)
Direct answer
1 inch = 25.4 mm
mm = inch × 25.4
Converter
Conversion formula
mm = inch × 25.4
inch = mm × 0.03937007874
Example: 10 inch = 10 × 25.4 = 254 mm.
Common conversion table
| inch | mm |
|---|---|
| 1 inch | 25.4 mm |
| 2 inch | 50.8 mm |
| 5 inch | 127 mm |
| 10 inch | 254 mm |
| 20 inch | 508 mm |
| 50 inch | 1,270 mm |
| 100 inch | 2,540 mm |
| 1,000 inch | 25,400 mm |
Conversion derivation
Express both inch and mm in the same base unit m (meter), then cancel the shared base unit.
- 1
Rewrite inch in the base unit
- 2
Rewrite mm in the base unit
- 3
Forward conversion
- 4
Reverse conversion
AI explanation for this conversion
This pre-generated explanation is schema-checked. Numeric results still come from the page formula and calculator.
Inch to Millimeter Conversion
This conversion factor of 25.4 allows you to change a measurement from inches to millimeters by multiplication. The factor is derived by expressing both units in terms of the base meter unit.
Definition
An inch is an imperial unit of length, and a millimeter is a metric unit of length. One inch is defined as exactly 0.0254 meters, while one millimeter is defined as 0.001 meters.
Principle
To find how many millimeters are in one inch, divide the meter value of an inch (0.0254) by the meter value of a millimeter (0.001), which gives 25.4.
Assumptions
- The conversion is based on the exact definition of an inch as 0.0254 meters.
- The conversion assumes a direct linear relationship between the units without temperature or material expansion considerations.
Cautions
- Rounding may be necessary depending on the precision required for your calculation.
- This conversion is for length only and does not apply to area or volume conversions.
FAQ
How many mm are in 1 inch?
1 inch = 25.4 mm.
How many mm are in 10 inch?
10 inch = 254 mm.
How many mm are in 100 inch?
100 inch = 2,540 mm.
What is the formula to convert inch to mm?
Use mm = inch × 25.4.
How many inch are in 1 mm?
1 mm = 0.03937007874 inch.
What should I check when converting inch to mm?
Use the conversion factor and round the result to the precision required by your calculation.