Fraction Decimal Chart

MM to Inches Fraction Chart

Convert millimeter measurements to decimal inches and nearest ruler fractions. This is useful when metric parts meet inch drawings.

MM to Inches Fraction Converter

Use the main calculator to enter fractions, decimals, mixed inch values, or millimeters. The chart below gives quick reference values for this page.

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Millimeters to Inch Fractions

Common millimeter values rounded to the nearest 1/64 inch.

MillimetersDecimal inchesNearest 1/32Nearest 1/64
1 mm 0.0394 in 1/32 3/64
2 mm 0.0787 in 3/32 5/64
3 mm 0.1181 in 1/8 1/8
4 mm 0.1575 in 5/32 5/32
5 mm 0.1969 in 3/16 13/64
6 mm 0.2362 in 1/4 15/64
8 mm 0.3150 in 5/16 5/16
10 mm 0.3937 in 13/32 25/64
12 mm 0.4724 in 15/32 15/32
15 mm 0.5906 in 19/32 19/32
16 mm 0.6299 in 5/8 5/8
20 mm 0.7874 in 25/32 25/32
25 mm 0.9843 in 31/32 63/64
25.4 mm 1.0000 in 1 1
30 mm 1.1811 in 19/16 19/16
40 mm 1.5748 in 25/16 101/64
50 mm 1.9685 in 63/32 63/32

Note: Values are based on 1 inch = 25.4 millimeters.

Millimeters to inches formula

  • Divide millimeters by 25.4.
  • Example: 9.525 mm divided by 25.4 = 0.375 in.
  • 0.375 in equals 3/8 in.

Rounding warning

  • A rounded inch fraction may not be exact.
  • Use the decimal value for machining.
  • Use the nearest fraction for quick ruler work.

All Conversion Charts

Decimal to Fraction ChartFraction to Decimal CalculatorDecimal Inch ChartInch Fraction CalculatorMM to Inches Fraction CalculatorInch Decimal to Fraction CalculatorFraction to Percent ChartFraction to MM ChartRuler Fraction ChartPrintable Fraction Decimal Chart1/16 Fraction Chart1/32 Fraction ChartPrintable 1/64 Chart