Inch to Millimeter Converter

1 Inch = 25.4 Millimeter

To convert inchs to millimeters, multiply by 25.4.

Converting inches to millimeters is essential in machining, industrial design, and woodworking to adapt imperial measurements to global metric standards.

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Formula

mm = in × 25.399999994

To convert Inch to Millimeter, use the formula displayed above.

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Inch to Millimeter: Quick Reference Table

Inch (in) Millimeter (mm)
0.001 0.0254
0.01 0.254
0.1 2.54
0.5 12.7
1 25.4
2 50.8
5 127
10 254
25 635
50 1270
100 2539.999999
250 6349.999998
500 12699.999997
1000 25399.999994

in to mm Formula and Examples

Direct Formula mm = in × 25.399999994
Inverse Formula in = mm × 0.03937
Mental Math Shortcut

Multiply the value by roughly 25.4 to calculate the equivalent amount in your head.

Common Inch to Millimeter Calculations

  • 5 in = 127 mm
  • 10 in = 254 mm
  • 50 in = 1270 mm
  • 100 in = 2539.999999 mm
  • 500 in = 12699.999997 mm

How to Convert Inch to Millimeter

How many millimeters are in a inch?
1 Inch (in) is equal to 25.4 Millimeter (mm). To convert inchs to millimeters, multiply your value by 25.4.
How do I convert inch to millimeter?
To convert Inch to Millimeter, use the formula: Millimeter = Inch × 25.4. For example, 5 in = 127 mm.
What is the formula for in to mm?
The formula is: mm = in × 25.4. This is based on the exact SI conversion factor. Use our calculator above to convert any value instantly.