Inches to MM Converter

Convert inches to millimeters with accurate formulas, examples and conversion tables.

Length conversion

Calculator

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Result

254 mm

10 in ≈ 254 mm

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Popular length conversions

Open a focused converter for a commonly searched length conversion.

Centimeters to Inches1 cm = 0.39370079 in Inches to Centimeters1 in = 2.54 cm Meters to Feet1 m = 3.2808399 ft Feet to Meters1 ft = 0.3048 m Kilometers to Miles1 km = 0.62137119 mi Miles to Kilometers1 mi = 1.609344 km Millimeters to Inches1 mm = 0.03937008 in Inches to Millimeters1 in = 25.4 mm

Conversion table

Common inches to millimeters values, generated from the selected units.

inches (in)	millimeters (mm)
1 inch	25.4 millimeters
5 inches	127 millimeters
10 inches	254 millimeters
20 inches	508 millimeters
50 inches	1,270 millimeters
100 inches	2,540 millimeters

Formula

Multiply the value in inches by 25.4 to get millimeters.

mm = in × 25.4

Example

Convert 10 inches:

10 in ≈ 254 mm

10 inches is approximately 254 millimeters.

Unit information

Concise reference information for the selected source and target units.

Inch (in)

Imperial

1 in = 0.0254 m

Definition: One international inch equals exactly 25.4 millimeters.
Usage: Common in the United States and for screens, hardware, and construction materials.

Millimeter (mm)

Metric

1 mm = 0.001 m

Definition: One millimeter is one-thousandth of a meter.
Usage: Used for precise dimensions, manufacturing, medicine, and rainfall.

Frequently asked questions

How many millimeters are in 1 inch?

1 inch equals 25.4 millimeters.

How do you convert inches to millimeters?

Multiply the value in inches by 25.4 to get millimeters. The formula is mm = in × 25.4.

What is 10 inches in millimeters?