Free Online Fraction Calculator

A fraction calculator performs arithmetic on two fractions and returns the result simplified to lowest terms with its decimal equivalent.

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Fraction 1
+
Fraction 2

How to Use This Calculator

  1. Pick the operation: +, −, ×, ÷, or Simplify.
  2. Enter the first fraction's numerator and denominator.
  3. Enter the second fraction if the operation needs two operands.
  4. Read the simplified result along with its decimal value.

What Is a Fraction Calculator?

Arithmetic on fractions follows fixed rules. Addition and subtraction need a common denominator first: a/b ± c/d = (ad ± bc) ÷ bd. Multiplication is straight across: a/b × c/d = ac ÷ bd. Division is multiplication by the reciprocal: a/b ÷ c/d = ad ÷ bc.

This tool handles all four operations plus a standalone simplify mode that reduces any fraction by dividing both numerator and denominator by their greatest common divisor. Results are always returned in canonical form — simplified, with the sign carried on the numerator, and with the decimal value shown for quick sanity checks.

A denominator of zero is rejected (not a valid fraction). Division by a zero fraction is flagged as undefined. Both numerator and denominator must be integers; convert mixed numbers to improper form first (1¾ = 7/4) before entering them.

Frequently Asked Questions

How do I add fractions with different denominators?
Find a common denominator, convert both fractions, then add numerators.
How do I simplify a fraction?
Divide numerator and denominator by their GCD (greatest common divisor). 8/12 = 2/3.
Can I convert fractions to decimals?
Yes, divide numerator by denominator. 3/4 = 0.75. Some fractions produce repeating decimals.

Published by the WeGotEveryTool team. We build and test every tool in-house and update pages when the underlying spec, formula, or recommendation changes.

Reviewed: May 2026. Disclaimer: this tool is provided as-is for general informational use. For decisions with material consequences (medical, legal, financial, security) verify results against a qualified professional source.

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