fraction calculator
Add, subtract, multiply or divide fractions — simplifies to lowest terms automatically. No sign-up.
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How fractions work
Addition
a/b + c/d = (a×d + c×b) / (b×d)
Subtraction
a/b − c/d = (a×d − c×b) / (b×d)
Multiplication
a/b × c/d = (a×c) / (b×d)
Division
a/b ÷ c/d = (a×d) / (b×c)
Simplify
Divide top & bottom by GCD(n, d)
FAQ
How do you add fractions with different denominators?
Find a common denominator, convert both fractions, then add the numerators. This calculator does it automatically.
How do you simplify a fraction?
Divide both the numerator and denominator by their GCD (greatest common divisor). The result is the fraction in lowest terms.
How do you divide fractions?
Flip the second fraction (take its reciprocal) and multiply. Example: 3/4 ÷ 1/2 = 3/4 × 2/1 = 6/4 = 3/2.
What is a mixed number?
A mixed number combines a whole number and a fraction, like 1½. This calculator shows mixed number form when the result is an improper fraction.
Is my data stored?
No — all calculations happen in your browser. Nothing is sent to any server.