HomepageConversionLength ConverterHow many Millimeters are in an Inch? atmiya25 in ConversionLength Converter How many Millimeters are in an Inch? 1 inch is equal to 25.4 millimeters: 1 ″ = 25.4 mm See also Kilojoules to kilocalories conversion Next Read: How many Millimeters are in a Centimeter? » atmiya25: Leave a Comment Related Post 1 gigahertz to hertz conversion 100 megahertz to hertz conversion 1 MHz to kHz conversion