Unit Converter
Millimeters to inches Converter
Convert millimeters (mm) to inches (in) with the exact factor, formula, four examples, and a quick browser calculator.
1 mm = 0.03937008 in
Formula and usage notes
This exact millimeters to inches page is built for quick lookup searches, product dimensions, shipping forms, schoolwork, and spreadsheet checks.
Formula: in = mm × 0.0393700787. The result is rounded for display, but the calculation uses the full factor shown here.
Practical examples
Practical examples 1
1 mm = 0.03937008 in
Practical examples 2
10 mm = 0.39370079 in
Practical examples 3
25.4 mm = 1 in
Practical examples 4
100 mm = 3.93700787 in
Frequently asked questions
How do I convert mm to in?
Multiply the millimeters value by 0.0393700787 to get inches.
Can I use this for product dimensions?
Yes. Keep the original value next to the converted value so reviewers can see the source unit.
Why do results differ slightly between sites?
Most differences come from rounding. This page calculates with the displayed factor and rounds only the visible result.