Enter two fractions and choose an operation. The answer is always reduced to its simplest form and also shown as a mixed number and a decimal. Use a negative numerator for negative fractions, and a denominator of 1 for whole numbers.
Formula
a/b + c/d = (a·d + c·b) ÷ (b·d)
Subtraction works the same way with a minus sign. Multiplication: a/b × c/d = (a·c) ÷ (b·d). Division: a/b ÷ c/d = (a·d) ÷ (b·c).
The result is simplified by dividing the numerator and denominator by their greatest common divisor.
Worked example
1/2 + 1/3: the common denominator is 6, so 3/6 + 2/6 = 5/6 ≈ 0.8333.
3/4 ÷ 1/8 = 3/4 × 8/1 = 24/4 = 6.
Frequently asked questions
How do I add fractions with different denominators?
Rewrite both fractions over a common denominator, add the numerators, then simplify. 1/4 + 1/6 = 3/12 + 2/12 = 5/12.
How do I divide fractions?
Multiply by the reciprocal of the second fraction (“keep, change, flip”): 2/3 ÷ 4/5 = 2/3 × 5/4 = 10/12 = 5/6.
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