Millimeters to Inches Converter — Convert mm to in Instantly

Millimeters to Inches Converter

Convert millimeters to inches quickly and accurately. Free online mm to in conversion tool with conversion table and formulas.

Step 1: Enter Millimeters

100 mm

Millimeter to Inch Conversion

1 millimeter equals 0.0393701 inches. Millimeters are part of the metric system while inches are part of the imperial system. This converter helps you switch between these measurement systems.

Step 2: Common Conversions

Millimeters
Inches
1 mm
0.0394 in
5 mm
0.1969 in
10 mm
0.3937 in
25.4 mm
1.0000 in
50 mm
1.9685 in

Conversion Formula

Inches = Millimeters ÷ 25.4
To convert millimeters to inches, divide the millimeter value by 25.4 (since 1 inch = 25.4 millimeters).

Conversion Results

Summary
Conversion Table
Conversion Formula

Millimeters to Inches Conversion

3.937 in
3 15/16 inches
Millimeters
100 mm
Inches
3.937 in
Feet & Inches
0 ft 3.937 in
Conversion Factor
25.4

Millimeters to Inches Conversion Table

Millimeters (mm) Inches (in) Inches (fraction) Feet & Inches

Conversion Formula & Details

Millimeter to Inch Formula

Inches = Millimeters ÷ 25.4
Since 1 inch is exactly equal to 25.4 millimeters, dividing the millimeter value by 25.4 gives you the equivalent in inches.

Example Calculation

100 mm to inches:
100 ÷ 25.4 = 3.937007874 inches
Rounded to 3 decimal places: 3.937 inches

Quick Reference

• 1 mm = 0.03937 in
• 10 mm = 0.3937 in
• 100 mm = 3.937 in
• 1000 mm = 39.37 in
• 25.4 mm = 1 in (exact)

Need Professional Measurement Help?

Connect with our measurement experts for detailed conversion solutions, engineering calculations, and professional measurement guidance.

Get Professional Help