Fraction Calculator
Add, subtract, multiply or divide two fractions and get the exact answer in lowest terms, as a mixed number where it applies, and as a decimal.
Results are exact: fractions are combined over a common denominator and reduced to lowest terms by dividing by the greatest common divisor. Use a minus sign for negative fractions (e.g. −3 over 4). To enter a mixed number like 2 1/3, convert it first: 2 × 3 + 1 = 7, so 7/3.
5/6
Simplified fraction
—
Mixed number
0.8333333333
Decimal
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How to use fraction calculator
- 1Type the numerator (top) and denominator (bottom) of the first fraction.
- 2Choose add, subtract, multiply or divide.
- 3Type the second fraction.
- 4Read the simplified fraction, mixed number and decimal.
About this tool
To add or subtract, the fractions are rewritten over a common denominator: a/b + c/d = (ad + bc)/bd. Multiplying multiplies tops and bottoms (a/b × c/d = ac/bd), and dividing multiplies by the reciprocal of the second fraction (a/b ÷ c/d = ad/bc). The result is then reduced to lowest terms by dividing top and bottom by their greatest common divisor — so 1/2 + 1/3 = 5/6, and 2/4 becomes 1/2.
Improper fractions (where the top is bigger than the bottom) are also shown as mixed numbers: 7/4 = 1 3/4. All arithmetic is done with exact whole numbers, even for very large values, so there's no rounding error in the fraction — only the decimal is rounded for display.
A denominator can't be zero, and you can't divide by a fraction equal to zero; the calculator explains the problem instead of returning a meaningless result. To enter a mixed number, convert it to an improper fraction first (2 1/3 = 7/3).
Frequently asked questions
Rewrite both fractions over a common denominator, add the numerators, then simplify. For 1/2 + 1/3: 3/6 + 2/6 = 5/6.
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