Convert millimeters to inches

Millimeter (mm) to inch (in). One millimeter equals 0.03937 inches.

1 mm =0.03937in (inches)

Formula

inches = millimeters ÷ 25.4

Millimeter to inch conversion table

MillimetersInchesInchesMillimeters
1 mm0.03937 in1 in25.4 mm
2 mm0.07874 in2 in50.8 mm
3 mm0.11811 in3 in76.2 mm
5 mm0.19685 in5 in127 mm
10 mm0.393701 in10 in254 mm
20 mm0.787402 in20 in508 mm
50 mm1.9685 in50 in1270 mm
100 mm3.937 in100 in2540 mm
500 mm19.685 in500 in12700 mm
1000 mm39.3701 in1000 in25400 mm

To convert millimeters to inches, divide the number of millimeters by 25.4. One millimeter equals 0.03937 inches, and one inch equals 25.4 millimeters, so the relationship is fixed and exact. As a worked example, 10 mm comes to 0.393701 in. Enter your own figure in the converter above to get an instant answer, or use the swap button to flip the direction. This is a length conversion, and like every tool on UnitGlide it runs locally in your browser with no account or upload required. The table further down shows a range of common millimeter values already worked out in inches, plus the reverse inch to millimeter direction, which is handy for quick reference or double-checking a result by hand.

Frequently asked questions

How many inches are in a millimeter?

One millimeter equals 0.03937 inches. The ratio is constant, so you can multiply any number of millimeters by 0.03937 to get inches.

What is the formula to convert millimeters to inches?

Use inches = millimeters ÷ 25.4. UnitGlide applies this exact formula for every value, so results stay accurate across the whole range.

How do I convert inches back to millimeters?

Go the other way by using one inch equals 25.4 millimeters. You can also press the swap button in the converter above to flip the direction in one click.

Is this millimeter to inch converter accurate?

Yes. It uses internationally defined SI conversion factors, as maintained by the BIPM, and all math runs in your browser so nothing is rounded away on a server. For everyday use the displayed precision is more than enough.

Related conversions

Embed this converter or use the API

Put this converter on your own site, or call the free JSON API. Full documentation is on the developers page.

Embed (iframe)

<iframe src="https://unitglide.net/embed/mm-to-in" width="360" height="200"
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        title="Millimeter to Inch converter"></iframe>
<p><a href="https://unitglide.net/convert/mm-to-in">Millimeter to Inch Converter</a> by UnitGlide</p>

API

https://unitglide.net/api/convert?from=mm&to=in&value=1