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1 in = 25.4 mm

1 in is 25.4 mm. To convert inches to millimeters, multiply by 25.4. Change the number below for any other value.

Quick examples
in
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Millimeters25.4 mm
The same number of millimeters in inches
0.0394 in

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      Inches to millimeters near 1 in

      Inches (in)Millimeters (mm)
      0.25 in6.35 mm
      0.375 in9.525 mm
      0.5 in12.7 mm
      0.75 in19.05 mm
      1 in25.4 mm
      1.25 in31.75 mm

      How it is worked out

      Millimeters = inches × 25.4
      1 in = 25.4 mm
      1 in × 25.4 = 25.4 mm

      Questions people ask

      How many mm is 1 in?

      1 in is 25.4 mm.

      How do I convert inches to millimeters?

      Multiply by 25.4. For example, 1 in × 25.4 = 25.4 mm.

      More in to mm conversions

      0.25 in0.375 in0.5 in0.75 in1 in1.25 in

      Converters

      Inches to Millimeters ConverterConvert in to mm instantly, with a conversion table.Millimeters to Inches ConverterConvert mm to in instantly, with a conversion table.