This chart converts metric measurements to fractional and decimal inch measurements. The metric to standard measurement conversion formula is 25.4 mm = 1 inch.

MM to inch fraction conversion calculations are approximate. For exact conversion from mm to inches a decimal inch measurement is more accurate. Fractional values are approximate while decimal values are exact. This is a measurement chart, for a socket size conversion chart visit the HOME page.

# MM to Inches Conversion Chart

Millimeters (mm) Inches (fraction) Inches (decimal)
1 mm 3/64 " 0.0394 "
2 mm 5/64 " 0.0787 "
3 mm 1/8 " 0.1181 "
4 mm 5/32 " 0.1575 "
5 mm 13/64 " 0.1969 "
6 mm 15/64 " 0.2362 "
7 mm 9/32 " 0.2756 "
8 mm 5/16 " 0.3150 "
9 mm 23/64 " 0.3543 "
10 mm 25/64 " 0.3937 "
20 mm 25/32 " 0.7874 "
30 mm 1 3/16 " 1.1811 "
40 mm 1 37/64 " 1.5784 "
50 mm 1 31/32 " 1.9685 "
60 mm 2 23/64 " 2.3633 "
70 mm 2 3/4 " 2.7559 "
80 mm 3 5/32 " 3.1496 "
90 mm 3 35/64 " 3.5433 "
100 mm 3 15/16 " 3.9370 "
* Fractional inches are rounded to the nearest 1/64

## MM to Inch Conversion F.A.Q.

### What size is 10 mm in inches?

10 mm is 25/64 fractional inches and 0.3937 decimal inches.

### What is the formula to convert mm to inches?

The formula to convert mm to inches is 1 inch = 25.4 mm

### How thick is 1mm in inches?

1 mm is equal to 3/64" (0.0394 in decimal inches)

### Are mm to fraction conversions exact or approximate?

When converting from Metric(mm) to Standard(inches) a fraction represents an approximate size. Fractions are rounded to the nearest usable value which is typically 1/64.

### What size is 40mm in inches?

40 mm = 1 37/64" = 1.5784 decimal inches.

### How do you convert mm to inches?

There are 25.4 millimeters per inch. To convert metric measurements to inches divide your mm measurement by 25.4.

### How do you convert inches to millimeters?

To convert inches to millimeters multiply inches by 25.4. The formula to convert inches to millimeters is length multiplied by 25.4.

## Related on Socket Size... ### Inch to MM Conversion Chart

A simple measurement chart to help you convert inches and fractions of inches to millimeters(mm). Standard to Metric chart includes decimal values.