| Inches (in) | Millimetres (mm) |
|---|
To convert inches to millimetres, multiply by 25.4.
The inch-to-millimetre relationship is exact by definition.
Multiply inches by 25.4 to convert to millimetres. For example, 3 inches equals 76.2 mm. This is an exact conversion used in engineering, manufacturing, and design.
To convert millimetres back to inches, divide by 25.4. Using exact factors helps when matching imperial tools with metric specifications.
Useful for hardware sizing, CAD drawings, 3D printing, machining, and product measurements where one source uses inches and another uses metric units.
1 inch equals exactly 25.4 mm.
0.5 inches equals 12.7 mm.
12 inches equals 304.8 mm.
Divide millimetres by 25.4.
Yes, inch-to-mm is defined exactly.