# MM to Inches — Convert Millimeters to Inches

Convert millimeters to inches instantly, with a quick reference table. Free, in your browser — no sign-up.

## How to convert millimeters to inches

Divide the length in millimeters by 25.4, because one inch is exactly 25.4 mm. For example, 100 mm ÷ 25.4 = 3.94 inches. Millimeters give fine precision, which is why this conversion shows up in technical work.

## Where you will use it

Millimeters-to-inches is an engineering and DIY staple: screw and bolt sizes, material thickness, 3D-printing dimensions, tool specs, and hardware sold in one system but used with tools in the other.

## How to

1. Enter the value in millimeters.
2. Read the result in inches.
3. Use the table for common values, or ⇄ to reverse.

## FAQ

**How many mm is 1 inch?**

1 inch is exactly 25.4 mm. To convert millimeters to inches, divide by 25.4.

**What is 10 mm in inches?**

10 mm = 0.3937 inches. Divide any millimeter value by 25.4.

**Is it free?**

Yes, completely free — no sign-up and no watermark.

**Is my data private?**

Yes — this tool runs entirely in your browser. Your files and text are never uploaded.


## Related

- [Unit Converter — Length, Weight & Temperature](/convert/unit-converter)
- [CM to Inches — Convert Centimeters to Inches](/convert/cm-to-inches)
- [Inches to CM — Convert Inches to Centimeters](/convert/inches-to-cm)
- [Feet to CM — Convert Feet to Centimeters](/convert/feet-to-cm)
- [CM to Feet — Convert Centimeters to Feet](/convert/cm-to-feet)
- [KM to Miles — Convert Kilometers to Miles](/convert/km-to-miles)
- [Miles to KM — Convert Miles to Kilometers](/convert/miles-to-km)
- [KG to LBS — Convert Kilograms to Pounds](/convert/kg-to-lbs)
- [LBS to KG — Convert Pounds to Kilograms](/convert/lbs-to-kg)
- [Grams to Ounces — Convert g to oz](/convert/grams-to-ounces)
- [Celsius to Fahrenheit — Convert °C to °F](/convert/celsius-to-fahrenheit)
- [Fahrenheit to Celsius — Convert °F to °C](/convert/fahrenheit-to-celsius)