Fraction ↔ Decimal Converter

Instantly convert between fractional inch measurements and their decimal and metric equivalents.

e.g. 3/4 · 1-1/2 · 7/16
Enter inches as a decimal
Decimal inches0.75"
Millimetres19.050 mm
Nearest 1/64"3/4"
Millimetres19.050 mm

Reference — 1/64″ to 1″

FractionDecimal"mm
1/8"0.1253.175
1/4"0.256.350
3/8"0.3759.525
1/2"0.512.700
5/8"0.62515.875
3/4"0.7519.050
7/8"0.87522.225
1/1"1.25.400

Reading the table

The reference table shows all common fractions (halves, quarters, eighths, sixteenths) to 1″. The Fraction → Decimal panel accepts any fraction you can type (e.g. 3/4, 1-1/2, 7/16) and converts it immediately to decimal inches and millimetres.

The Decimal → Fraction panel finds the nearest fraction to the precision you choose (1/8″ through 1/64″). Useful when a drawing gives a decimal dimension and you need to set a marking gauge or dial caliper.