About the Add Fractions Calculator
Add two fractions or mixed numbers and get the answer in simplest form, as a mixed number and as a decimal, with every step shown.
Also known as: add fractions, adding fractions, fraction addition.
How to use this calculator
- Enter first fraction, second fraction.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Open “Step-by-step” to see how the answer was worked out.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
a/b + c/d = (ad + bc) / bd
Worked example
Using the values pre-filled in the calculator above:
- First fraction: 1/3
- Second fraction: 2/5
the calculator returns:
- Answer: 11/15
- Mixed number: 11/15
- Decimal: 0.7(3)
Working
Least common denominator: LCD(3, 5) = 151/3 = 5/15, 2/5 = 6/155 + 6 = 11 over 15Simplest form: 11/15