Fraction calculator
Add, subtract, multiply, or divide two fractions, simplified for you.
Result
How to add, subtract, multiply, and divide fractions
This calculator works with two fractions and any of the four operations, then reduces the answer to lowest terms and shows the decimal. To add or subtract, the fractions are put over a common denominator first; to multiply, you multiply across; to divide, you flip the second fraction and multiply.
The rules
a/b × c/d = ac / bd
a/b ÷ c/d = ad / bc
Worked example
1/2 + 1/3 share a denominator of 6: that is 3/6 + 2/6 = 5/6 (about 0.833). Multiplying instead gives 1/2 × 1/3 = 1/6, and dividing gives 1/2 ÷ 1/3 = 3/2.
Frequently asked questions
How do I add or subtract fractions?
Give both fractions the same denominator, then add or subtract the numerators. The calculator finds the common denominator and simplifies the result for you.
How do I multiply fractions?
Multiply the numerators together and the denominators together, then simplify. For example, 2/3 × 3/4 = 6/12, which reduces to 1/2.
How do I divide fractions?
Flip the second fraction and multiply. So 1/2 ÷ 1/4 becomes 1/2 × 4/1 = 4/2 = 2.
How do I simplify a fraction?
Divide the numerator and denominator by their greatest common divisor. The calculator always returns the answer in lowest terms.
How do I convert a fraction to a decimal?
Divide the numerator by the denominator. The calculator shows the decimal alongside the simplified fraction.