Calculator
Fraction Calculator
Add, subtract, multiply or divide two fractions. The result is simplified automatically.
How are fractions added, subtracted, multiplied and divided?
Each operation on two fractions follows its own rule, and the result is automatically simplified to its lowest terms — so 2/4 becomes 1/2 rather than being left unreduced.
Frequently asked questions
How do you add or subtract fractions?
Fractions need a common denominator before adding or subtracting. This calculator cross-multiplies: for a/b + c/d, the result is (a×d + c×b) / (b×d), which always produces a valid common denominator even if it isn't the smallest one — simplification afterward reduces it to lowest terms.
How do you multiply fractions?
Multiply straight across: numerator times numerator, denominator times denominator. a/b × c/d = (a×c) / (b×d). No common denominator is needed for multiplication, unlike addition and subtraction.
Why does dividing fractions flip the second one?
Dividing by a fraction is the same as multiplying by its reciprocal — a/b ÷ c/d equals a/b × d/c. This works because dividing by a number and multiplying by its reciprocal are mathematically equivalent operations for any nonzero number.
How is the result simplified?
The calculator finds the greatest common divisor (GCD) of the numerator and denominator using the Euclidean algorithm, then divides both by it. This guarantees the smallest possible equivalent fraction, and the decimal equivalent shown alongside it is just the numerator divided by the denominator.