Fraction Calculator

Add, subtract, multiply or divide two fractions and get the answer simplified, as a decimal and as a percentage.

How fraction is worked out

Enter two fractions and an operation and this calculator returns the result in lowest terms, along with its decimal and percentage values.

It handles the common headache of finding a common denominator and simplifying for you.

Step by step

  1. Enter the first fraction’s numerator and denominator.
  2. Choose an operation.
  3. Enter the second fraction and read the simplified result.

The formula

add/sub: a/b ± c/d = (a·d ± c·b) ÷ (b·d) multiply: a·c ÷ b·d · divide: a·d ÷ b·c, then simplify

Worked example

The calculator opens with a operation of +. On those figures the result is 5/6. Underneath, Decimal comes out at 0.8333 and As percent at 83.33%. Change any field and every figure updates as you type.

Frequently asked questions

How do I add fractions?
Give them a common denominator, add the numerators, then simplify. This tool does all three steps automatically.
How is the fraction simplified?
By dividing the numerator and denominator by their greatest common divisor, giving lowest terms.
Can it handle improper fractions?
Yes — any whole-number numerator and denominator work, and the result is shown in lowest terms plus decimal form.