Millimeters to Inches Converter
Convert millimeters to inches instantly. One millimeter equals exactly 0.03937008 inches. Type in either box to convert both ways, then use the chart, worked examples and everyday sizes below.
How to convert millimeters to inches
Worked example: convert 64 millimeters to inches. Using inches ← millimeters × 0.03937007874, we get 64 × 0.03937007874 = 2.519685 in. To check the result, convert back: 2.519685 in ÷ 0.03937007874 = 64 mm.
Millimeters to inches chart
| Millimeters (mm) | Inches (in) |
|---|---|
| 1 mm | 0.03937008 in |
| 2 mm | 0.07874016 in |
| 3 mm | 0.1181102 in |
| 4 mm | 0.1574803 in |
| 5 mm | 0.1968504 in |
| 6 mm | 0.2362205 in |
| 8 mm | 0.3149606 in |
| 10 mm | 0.3937008 in |
| 12 mm | 0.4724409 in |
| 15 mm | 0.5905512 in |
| 20 mm | 0.7874016 in |
| 25 mm | 0.984252 in |
| 30 mm | 1.181102 in |
| 40 mm | 1.574803 in |
| 50 mm | 1.968504 in |
| 75 mm | 2.952756 in |
| 100 mm | 3.937008 in |
| 150 mm | 5.905512 in |
| 200 mm | 7.874016 in |
| 250 mm | 9.84252 in |
| 500 mm | 19.68504 in |
| 1,000 mm | 39.37008 in |
Inches to millimeters (reverse)
| Inches (in) | Millimeters (mm) |
|---|---|
| 1 in | 25.4 mm |
| 2 in | 50.8 mm |
| 5 in | 127 mm |
| 10 in | 254 mm |
| 20 in | 508 mm |
| 50 in | 1,270 mm |
| 100 in | 2,540 mm |
| 250 in | 6,350 mm |
| 500 in | 12,700 mm |
| 1,000 in | 25,400 mm |
About the millimeter and the inch
A millimeter (millimetre) is one thousandth of a meter and is the everyday unit for small parts: screw diameters, phone thickness, rainfall totals and camera sensor sizes. A credit card is 0.76 mm thick, which gives a feel for the scale.
The inch is an imperial and US customary unit equal to one twelfth of a foot. It is used for screen sizes, tire and wheel dimensions, plumbing pipes, lumber and many tools in the US, UK and Canada.
One inch equals 25.4 millimeters, which makes the inch the longer unit of the two.
Everyday sizes in millimeters and inches
| Everyday example (approximate) | In millimeters | In inches |
|---|---|---|
| The thickness of a credit card | 0.76 mm | 0.029921 in |
| The long side of an A4 sheet of paper | 297 mm | 11.693 in |
| A typical adult's height | 1,700 mm | 66.929 in |
| A standard interior door | 2,032 mm | 80 in |
| A double-decker bus length | 11,000 mm | 433.07 in |
| An Olympic swimming pool | 50,000 mm | 1,968.5 in |
Millimeters to inches FAQ
How many inches are in one millimeter?
One millimeter equals exactly 0.03937007874 inches. In the other direction, one inch equals 25.4 millimeters.
How do I convert millimeters to inches without a calculator?
convert 64 millimeters to inches. Using inches ← millimeters × 0.03937007874, we get 64 × 0.03937007874 = 2.519685 in. To check the result, convert back: 2.519685 in ÷ 0.03937007874 = 64 mm. For a quick estimate, round the factor to 0.039. Then 64 mm is about 2.496 in, compared with the exact 2.51969 in (an error of 0.94%). That is close enough for planning, but use the calculator above when the number matters.
What is a double-decker bus length in inches?
A double-decker bus length is about 11,000 millimeters, which is 433.07 inches. Treat that as an approximate everyday figure rather than an official measurement.
Are the millimeters and inches the same in every country?
The millimeter is exactly 0.001 m in every country that uses the metric system. Since the 1959 international agreement the inch is exactly 25.4 millimeters in the US, UK, Canada and Australia.