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Decimal to Fraction

Convert a decimal to a fraction (with carpentry/machining sizes).

As a fraction
5/8
closest match within 1/64

Best approximation: 5/8

Nearest 1/16 (carpentry): 5/8

Nearest 1/32 (machining): 5/8

Common ruler readings

  • /2
    1/2
  • /3
    2/3
  • /4
    2/3
  • /8
    5/8
  • /16
    5/8
  • /32
    5/8
  • /64
    5/8

Uses continued-fraction expansion to find the simplest fraction within a given denominator limit. Useful for converting metric measurements to fractional inches, machining tolerances, or dough hydration percentages back to weights.

About

Type a decimal. The tool returns the simplest fraction within a denominator limit using continued fraction expansion. Also shows nearest 1/16 (carpentry) and 1/32 (machining), plus all common ruler readings.

How to use

  1. Type a decimal value.
  2. Pick the denominator limit.

FAQ

Why continued fractions?+

They give the best rational approximation for any denominator. Better than simple rounding because the answer is always a fraction in lowest terms.