About the Fraction Calculator
Do arithmetic with fractions, mixed numbers like 1 1/2, and decimals. Every result is reduced to lowest terms and also shown as a mixed number, decimal and percentage.
Key features
- Add, subtract, multiply and divide fractions
- Mixed numbers (1 1/2), whole numbers and decimals accepted
- Results always reduced to lowest terms
- Shown as a fraction, mixed number, decimal and percent
- Reciprocal included
- Negative fractions supported
Fraction arithmetic made easy
Fractions turn up in recipes, woodworking, measurements and homework. Enter two fractions, pick an operation, and get a simplified answer with its mixed-number, decimal and percent forms.
How each operation works
| Operation | Rule | Example |
|---|---|---|
| Add | a/b + c/d = (ad + bc) / bd | 1/2 + 1/3 = 5/6 |
| Subtract | a/b − c/d = (ad − bc) / bd | 3/4 − 1/6 = 7/12 |
| Multiply | a/b × c/d = ac / bd | 2/3 × 3/4 = 1/2 |
| Divide | a/b ÷ c/d = ad / bc | 3/4 ÷ 1/2 = 1 1/2 |
Simplifying fractions
A fraction is in lowest terms when the numerator and denominator have no common factor except 1. The calculator divides both by their greatest common divisor (GCD): 18/24 → GCD 6 → 3/4.
Mixed numbers and improper fractions
- Improper fraction: the numerator is larger than the denominator, e.g. 13/6.
- Mixed number: a whole number plus a proper fraction, e.g. 2 1/6.
- To convert 2 1/6 to an improper fraction: 2 × 6 + 1 = 13, giving 13/6.
Examples from everyday life
- Recipes: 1 1/2 cups × 2/3 (making two-thirds of a recipe) = 1 cup.
- Woodworking: 5 3/8 in − 2 3/4 in = 2 5/8 in.
- Time: 3/4 hour + 1/3 hour = 13/12 hours = 1 hour 5 minutes.
Related calculators
Simplify ratios with the Ratio Calculator, or convert results to percentages with the Percentage Calculator.
How to use the Fraction Calculator
- Enter your numbers in the fields above. Units and options can be changed at any time.
- The result updates instantly as you type; there's no calculate button to press.
- Check the breakdown under the main result for the details behind the number.
- Adjust the inputs to compare scenarios, for example a different rate or term.