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Fraction Calculator

Add, subtract, multiply, or divide two fractions, with the result automatically simplified and shown as a decimal too — instantly, in your browser.

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Add, subtract, multiply, or divide two fractions. The result is automatically simplified to lowest terms, with the decimal equivalent shown alongside. Enter your fractions below and click Calculate.

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Formulas

  • Add: a/b + c/d = (ad + cb) / bd
  • Subtract: a/b − c/d = (ad − cb) / bd
  • Multiply: a/b × c/d = ac / bd
  • Divide: a/b ÷ c/d = ad / bc

Every result is reduced to lowest terms using the greatest common divisor. Worked example: 1/2 + 1/3 = (1×3 + 1×2) / (2×3) = 5/6.

FAQs

Why is my result already simplified?

This tool always reduces the result to lowest terms by dividing both the numerator and denominator by their greatest common divisor, so 2/4 becomes 1/2 automatically.