Fraction Calculator
Add, subtract, multiply, or divide two fractions. Get the answer in lowest terms, as a decimal, and as a mixed number.
How to use this calculator
Enter the numerator and denominator of each fraction, choose an operation (+ − × ÷), and the calculator shows the simplified result, the decimal value, and the mixed-number form.
How fraction math works
Adding and subtracting fractions requires a common denominator; multiplying multiplies straight across; dividing means multiplying by the reciprocal of the second fraction. The answer is then reduced to lowest terms by dividing out the greatest common divisor.
Worked example
1/2 + 1/3: the common denominator is 6, so it becomes 3/6 + 2/6 = 5/6 (≈ 0.8333). 3/2 would display as the mixed number 1 1/2.
The rules
a/b + c/d = (ad + cb)/bd · a/b − c/d = (ad − cb)/bd · a/b × c/d = ac/bd · a/b ÷ c/d = ad/bc
Frequently asked questions
How do you add or subtract fractions?
Give both fractions a common denominator, then add or subtract the numerators. For 1/2 + 1/3, use sixths: 3/6 + 2/6 = 5/6. This calculator finds the common denominator and simplifies for you.
How do you multiply and divide fractions?
To multiply, multiply the numerators and the denominators: 1/2 × 1/3 = 1/6. To divide, flip the second fraction and multiply: 1/2 ÷ 1/3 = 1/2 × 3/1 = 3/2.
How is the result simplified?
The calculator divides the numerator and denominator by their greatest common divisor, reducing the fraction to lowest terms — for example 4/8 becomes 1/2.
What is a mixed number?
A mixed number combines a whole number and a proper fraction, like 1 1/2 instead of 3/2. The calculator shows the mixed-number form when the result is greater than one.