Fraction Calculator
Add, subtract, multiply, or divide two fractions, then read the simplified fraction, a mixed number, and a decimal.
About this calculator
Fraction arithmetic is exact when you keep numerators and denominators as integers. This calculator performs the four basic operations and reduces the answer to lowest terms.
How to calculate
Enter the two numerators and denominators, choose an operation, and calculate. Denominators must not be zero. The result is shown as a simplified fraction and as a decimal.
a/b + c/d = (ad + bc) / bd
a/b × c/d = ac / bd
a/b ÷ c/d = ad / bc
When to use it
- Checking homework steps
- Scaling a recipe that uses cups as fractions
Examples
Adding 1/2 and 1/3
1/2 + 1/3 = 3/6 + 2/6 = 5/6.
Common fractions as decimals
| Fraction | Decimal |
|---|---|
| 1/2 | 0.5 |
| 1/3 | 0.333… |
| 1/4 | 0.25 |
| 2/3 | 0.666… |
| 3/4 | 0.75 |
| 1/8 | 0.125 |
FAQ
Why do fractions need a common denominator to add?
Addition combines like parts. Converting both fractions to the same denominator makes the pieces the same size so the numerators can be added.
Can the result be an improper fraction?
Yes. The calculator also shows a mixed number when the absolute value of the result is greater than 1.