Fraction Calculator

Simplify fractions and show decimal equivalent.

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Formula

Simplified fraction = (numerator ÷ GCD) / (denominator ÷ GCD)

GCD is the greatest common divisor of the numerator and denominator. Dividing both parts by the GCD yields the fraction in lowest terms. The decimal form is simply numerator ÷ denominator.

Worked example

3/12 shares a common factor of 3, so it simplifies to 1/4 — as a decimal that's 0.25, or 25% of a whole.

Where this can give the wrong answer

  • A denominator of zero is rejected — division by zero is undefined, even if the numerator is also zero.
  • Negative signs are preserved in the simplified form (e.g. −3/12 becomes −1/4); the GCD is computed on absolute values, then the sign is applied to the result.
  • Improper fractions (numerator larger than denominator) are simplified but not converted to mixed numbers — 7/4 stays as 7/4, with decimal 1.75.

FAQ

No — it takes a numerator and denominator you enter and simplifies them. To go from a decimal like 0.375 to 3/8, you'd need to reason about place value or use a dedicated decimal-to-fraction tool.