Decimal to Fraction Inch Converter

Convert decimal caliper readings to fractional drill/wrench sizes and back. Choose precision down to 1/128. Fractional inch chart included.

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A caliper reads 0.265" — what fraction is that? Or you need to drill a 23/64" hole and the spec is in thousandths. Decimal-to-fraction (and back) conversion you'll do a hundred times in a shop.

Common decimal ↔ fraction equivalents

  • 1/16" = 0.0625"
  • 1/8" = 0.125"
  • 3/16" = 0.1875"
  • 1/4" = 0.250"
  • 5/16" = 0.3125"
  • 3/8" = 0.375"
  • 7/16" = 0.4375"
  • 1/2" = 0.500"
  • 5/8" = 0.625"
  • 3/4" = 0.750"

Round to nearest 1/64" for general shop work; 1/128" for precision machining.