How to use the fraction calculator
Enter the numerator and denominator for each fraction, then choose addition, subtraction, multiplication, or division. Denominators cannot be zero.
Fraction arithmetic
The result is reduced by dividing the numerator and denominator by their greatest common divisor.
Example: Ava adds two recipe quantities
Ava combines 1/2 cup and 1/4 cup. Converting 1/2 to 2/4 gives 2/4 + 1/4 = 3/4 cup. The decimal equivalent is 0.75.
For division, the second fraction is inverted before multiplication. A zero numerator in that second fraction would mean division by zero and has no defined result.
Enter each fraction as a numerator and denominator
For 1/2 + 1/3, enter 1 and 2 for the first fraction, then 1 and 3 for the second. The simplified answer is 5/6.
A denominator cannot be zero. To divide fractions, the second numerator also must not be zero. Negative signs can be entered in either part of a fraction.
Handle mixed numbers and negative fractions
Rewrite a mixed number as an improper fraction before entering it: 2½ becomes 5/2. A negative numerator can represent a negative fraction, such as -3/4.
Division uses the reciprocal of the second fraction. Dividing 1/2 by 3/4 gives 1/2 × 4/3 = 2/3. A zero denominator is undefined, and division by a zero-valued fraction is also undefined.
Assumptions and limitations
What the estimate assumes
This tool works with numeric fractions, not algebraic expressions.
Fraction Calculator FAQs
How do you add fractions with different denominators?
Rewrite the fractions using a common denominator, add the numerators, then simplify.
How do you divide fractions?
Multiply the first fraction by the reciprocal of the second fraction.
Why can't a denominator be zero?
Division by zero is undefined, so a fraction cannot have a zero denominator.
Does the calculator simplify fractions?
Yes. It reduces the final numerator and denominator by their greatest common divisor.
For arithmetic and educational use.