Fraction calculator

Work with two fractions and get the result simplified, as a mixed number and as a decimal.

How it works

To add or subtract fractions you need a common denominator: cross-multiply and add the numerators. To multiply, multiply tops and bottoms. To divide, multiply by the flipped fraction.

The result is simplified by dividing top and bottom by their greatest common divisor.

a/b + c/d = (a·d + c·b) / (b·d)
a/b × c/d = (a·c) / (b·d)
a/b ÷ c/d = (a·d) / (b·c)

Frequently asked questions

How do I simplify a fraction?

Divide top and bottom by the greatest common divisor. 18/24: the GCD is 6, so it becomes 3/4.

What is a mixed number?

A whole number plus a fraction, used for fractions greater than 1: 7/4 = 1 ¾.

How do I turn a decimal into a fraction?

Choose “Decimal to fraction”: 0.375 = 375/1000 = 3/8.

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