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Inches to mm Converter (Inches to Millimeters)

1 inch = 25.4 millimeters. To convert in to mm, multiply by 25.4.

⇄

100 in = 2,540 mm

1 in
25.4 mm
1 mm
0.03937 in
10 in
254 mm
100 in
2,540 mm

How to convert Inches to mm

1 inch equals 25.4 millimeters, so the conversion is a single multiplication.

mm = in × 25.4

Example: 150 in × 25.4 = 3,810 mm.

About the inch and the millimeter

Inch (in)

The inch has been exactly 2.54 cm since the 1959 international yard and pound agreement. In the US it's used for screens, lumber, tire sizes and height.

Millimeter (mm)

A millimeter is one thousandth of a meter, the unit used on rulers, tools and technical drawings.

1 inch in every length unit

Centimeters2.54 cmMeters0.0254 mFeet0.08333 ft
Kilometers0.0000254 km
Miles0.00001578 mi
Millimeters25.4 mm
Yards0.02778 yd
Nautical Miles0.00001371 nmi
Micrometers25,400 µm
Nanometers25,400,000 nm
Mils1,000 mil
Hands0.25 hh
Fathoms0.01389 ftm
Rods0.005051 rd
Chains0.001263 ch
Furlongs0.0001263 fur
Astronomical Units1.698e-13 au
Light-Years2.685e-18 ly
mm to InchesReverse conversioncm to Inches1 cm = 0.3937 inInches to cm1 in = 2.54 cmInches to Feet1 in = 0.08333 ftFeet to Inches1 ft = 12 incm to mm1 cm = 10 mmmm to cm1 mm = 0.1 cmMeters to Inches1 m = 39.3701 inInches to Meters1 in = 0.0254 mmm to Feet1 mm = 0.003281 ftFeet to mm1 ft = 304.8 mm

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Inches to mm FAQ

How many millimeters are in a inch?

1 inch = 25.4 millimeters.

How many inches are in a millimeter?

1 millimeter = 0.03937007874 inches.

How do I convert in to mm?

Use mm = in × 25.4. For example, 10 in = 254 mm.

Can I print this Inches to mm chart?

Yes. Use "Print / Save PDF" next to the converter for a one-page chart, or "Download CSV" to open it in Excel or Google Sheets.