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Conversion Formula:
mm = in × 25.4
Convert Inch to Millimeter (in to mm) instantly with accurate, readable results.
Use our Length Unit Converter to quickly convert between meters, kilometers, feet, inches, miles, and more. This powerful unit conversion tool supports both metric and imperial systems, making it ideal for travel, engineering, education, and everyday use. Whether you're calculating distances or comparing measurements, our length unit conversion calculator ensures fast and accurate results every time.
From unit
Inch (in) — Imperial/US unit defined exactly as 25.4 millimeters
Standard in manufacturing and consumer specs in the US, including displays and lumber. Defined metrically for exact conversions.
- Symbol: in
- System: Imperial/US customary
- Exact relations: 1 in = 25.4 mm = 2.54 cm = 0.0254 m (exact)
- Other relations: 12 in = 1 ft, 36 in = 1 yd
- Typical examples: screen sizes, pipe/nominal lumber sizes, drill bits
To unit
Millimeter (mm) — one thousandth of a meter
Used for precision work, machining, and rainfall depth reporting. Suitable for tolerances and tiny parts.
- Symbol: mm
- System: SI derived unit
- Exact relations: 1 mm = 0.001 m = 0.1 cm
- Imperial/US equivalents: 1 mm = 0.0393700787 in
- Typical examples: screw diameters, gasket thickness, PCB traces