Millimeters to Inches

Convert millimeters to inches instantly — divide the millimeters by 25.4. Type in either box to convert both ways. Useful for hardware, screws, print sizes and small dimensions when a measurement comes in millimeters but you think in inches.

Millimeters to Inches conversion table

Millimeters (mm) Inches (in)
1 mm 0.0393701 in
5 mm 0.19685 in
10 mm 0.393701 in
12 mm 0.472441 in
20 mm 0.787402 in
25 mm 0.984252 in
50 mm 1.9685 in
100 mm 3.93701 in
300 mm 11.811 in

How to convert millimeters to inches

To convert millimeters to inches, divide the millimeters by 25.4. For example, 1 mm equals 0.0393701 in. The calculator above runs the exact factor at full precision and updates as you type, and the swap button flips the direction so you can go from inches back to millimeters just as quickly.

Frequently asked questions

How do you convert millimeters to inches?

To convert millimeters to inches, divide the millimeters by 25.4. For example, 1 mm is 0.0393701 in. The calculator above does this for you the moment you type — enter a value on the left and the inches result appears on the right, and you can type in either box to convert in the opposite direction. Every result uses the exact internationally defined factor, not a rounded shortcut, so the numbers are accurate enough for schoolwork, cooking, travel and engineering alike.

How many inches are in 1 mm?

There are 0.0393701 in in 1 mm, and millimeters scale to inches in that same fixed ratio at any size. The conversion table on this page lists the most common values — 1 mm is 0.0393701 in, and the table continues up to 300 mm = 11.811 in — so you can read off everyday amounts at a glance without typing anything. Values that fall between those rows convert just as exactly, because the calculator carries the full factor rather than the rounded figures printed here.

Is this mm to in converter accurate?

Yes — this mm to in converter is accurate. It uses the precise, internationally agreed conversion factor rather than a rounded approximation, and the math runs at full double precision in your browser, with results shown to six significant figures. Useful for hardware, screws, print sizes and small dimensions when a measurement comes in millimeters but you think in inches.

Is the millimeters to inches converter free?

Yes — the millimeters to inches converter is completely free, with no sign-up and no limit on how many conversions you run. Every calculation happens locally in your browser, so nothing you type is uploaded or stored. For other units, the full LK Forge unit converter covers length, weight, temperature, volume and speed in one place.

More conversions

Inches → MillimetersMeters → FeetFeet → MetersGrams → OuncesOunces → GramsMilliliters → Fluid Ounces All units →

Reference: full unit conversion chart · metric vs imperial, explained