Adding Fractions Calculator

Add two fractions quickly and see the full step-by-step process including common denominator calculation.

How to Add Fractions

Adding fractions requires a common denominator. Our tool finds the Least Common Denominator (LCD) for you and shows every step of the conversion and addition process.

Like Denominators

a/c + b/c = (a+b)/c

Just add the numerators

Unlike Denominators

a/b + c/d = (ad + bc) / bd

Find common denominator first

Examples

Add 1/2 + 1/3

1LCD of 2 and 3 is 6
2Convert: 3/6 + 2/6
3Add: (3+2)/6 = 5/6

Frequently Asked Questions

What is the LCD?

The Least Common Denominator is the smallest number that both denominators can divide into evenly.

Do I add the denominators?

No! You only add the numerators (the top numbers) once the denominators are the same.