Math & Scientific

Fraction Calculator

Add, subtract, multiply, or divide two fractions and get the simplified result.

How fraction operations work

Adding or subtracting fractions requires a common denominator: cross-multiply so both fractions share the same denominator, then add or subtract the numerators.

Multiplying fractions is more direct — multiply the numerators together and the denominators together. Dividing is the same as multiplying by the reciprocal (flip the second fraction).

Worked example

1/2 + 1/3: cross-multiplying gives a common denominator of 6, so this becomes 3/6 + 2/6 = 5/6, which is already in its simplest form.

Frequently asked questions

Why does the calculator simplify the answer?

Fractions are conventionally given in their lowest terms — the largest common factor of the numerator and denominator is divided out so the fraction can't be reduced any further.

Can I use negative numbers?

Yes. A negative numerator or denominator is handled correctly, and the sign is normalised onto the numerator in the simplified result.

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