Convert MM to INCHES, Free
Type any MM value and see the INCHES result instantly. No button press needed.
How to convert MM to INCHES
Millimeters appear constantly in hardware specs, woodworking plans, mechanical drawings, and product dimensions from manufacturers in metric countries. If your ruler, drill bit set, or bolt kit is labeled in inches, you need to translate those millimeter figures before you can work with them. At 25.4 mm per inch, the math is simple enough for round numbers but tedious for anything precise.
Type any millimeter measurement into BoltConverter and the inch equivalent appears immediately, shown in decimal form and broken out into the nearest fractional inch for workshop use. No rounding errors, no unit confusion, and no calculator required for anything from bolt diameters to board widths.
Enter millimeters
Type the mm value you want to convert. Decimal values like 12.7 mm are supported.
See inches instantly
The result in decimal inches and the nearest fractional equivalent updates as you type.
Use the fractional reading
For workshop or hardware use, check the fractional inches column (e.g. 1/2 in or 25/64 in) for the closest standard fraction.
Copy your result
Select and copy the value you need, or note it before returning to your work.
Frequently asked questions
How many mm is 1 inch?
One inch equals exactly 25.4 millimeters. To convert mm to inches, divide by 25.4.
What is 10 mm in inches?
10 mm equals approximately 0.394 inches, which is close to 25/64 of an inch or roughly 3/8 of an inch.
What is 25 mm in inches?
25 mm equals 0.984 inches, very close to 1 inch (which would be exactly 25.4 mm).
Why does the result show a fraction?
Imperial measurements in workshops and hardware are often expressed as fractions (1/8, 3/16, 7/32, etc.). The fractional column shows the closest standard fraction to help you pick the right drill bit, bolt, or fitting.
Is the conversion exact?
Yes. The ratio 1 inch = 25.4 mm is an exact international definition, not an approximation.