Fraction Calculator
Add, subtract, multiply and divide fractions, with the answer simplified and shown as a decimal.
1/2 + 1/3
5/6
simplified
Unsimplified5/6
Simplified5/6
Mixed number5/6
Decimal0.833333
Percentage83.3333%
About the Fraction Calculator
Enter two fractions and an operation. The result comes back fully simplified, as a mixed number where appropriate, and as a decimal — so it doubles as a fraction-to-decimal converter.
Formula
Addition and subtraction use a common denominator: a/b ± c/d = (a·d ± c·b) / (b·d). Multiplication is a·c / b·d. Division multiplies by the reciprocal. The result is then divided by the greatest common divisor.
Frequently Asked Questions
Divide the numerator and denominator by their greatest common divisor. For 18/24 the GCD is 6, so the simplified form is 3/4.
Divide the numerator by the denominator. 3/8 becomes 3 ÷ 8 = 0.375. Some fractions, like 1/3, produce a repeating decimal that never terminates.
Because the denominator defines the size of each part. Thirds and quarters are different-sized pieces, so they cannot be counted together until both are rewritten as twelfths.
A whole number combined with a proper fraction, like 1½. It is another way of writing an improper fraction such as 3/2, where the numerator exceeds the denominator.
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