How to Convert Inches to Millimeters Converting inches to millimeters is simple using a fixed conversion factor. One inch equals exactly 25.4 millimeters. The Mathematical Formula To convert inches to millimeters, multiply the inches by 25.4: Millimeters = Inches � 25.4 Inches to Millimeters Conversion Table Inches (in) Millimeters (mm) Common Use Case 1 in25.4 mmExact equivalence 12 in (1 ft)304.8 mmOne foot 39.37 in1000 mmOne meter 66.93 in1700 mmAverage height 70.87 in1800 mmTall height Frequently Asked Questions What is 1 inch in millimeters? 1 inch equals 25.4 millimeters exactly. How do I convert inches to mm? Multiply the number of inches by 25.4 to get millimeters.
