Calculate With Fractions and Mixed Numbers
This fraction calculator adds, subtracts, multiplies and divides fractions and mixed numbers. Enter each fraction (with an optional whole number for mixed numbers), choose an operation, and get the answer in lowest terms, as a mixed number and as a decimal. The steps are shown so you can follow the work or check homework.
How to Do Fraction Math
Example: 2 1/3 + 1 3/4 = 7/3 + 7/4 = 28/12 + 21/12 = 49/12, which is 4 1/12 or about 4.0833.
Example: 3/4 ÷ 2/5 = 3/4 × 5/2 = 15/8 = 1 7/8 = 1.875.
- Add or subtract: rewrite both fractions with the least common denominator, then add or subtract the numerators.
- Multiply: multiply the numerators together and the denominators together.
- Divide: flip the second fraction (use its reciprocal) and multiply.
- Mixed numbers: convert to improper fractions first. For example, 2 1/3 = (2 × 3 + 1)/3 = 7/3.
- Always simplify the result by dividing the top and bottom by their greatest common divisor.
Where Fractions Come Up
Fractions are everywhere in daily life: doubling or halving recipes, measuring wood and fabric in inches, splitting costs, reading tape measures and working with probabilities. To reduce a single fraction to lowest terms, try our Fraction Simplifier.
Frequently Asked Questions
How do I enter a mixed number?
Type the whole number in the left box and the fraction in the numerator and denominator boxes. For 3 1/2, enter 3, then 1 over 2. Leave the whole-number box empty for a simple fraction.
How do I enter a negative fraction?
For a negative mixed number, make the whole number negative, such as −2 for −2 1/3. For a negative simple fraction, make the numerator negative, such as −3 over 4.
What is the least common denominator?
It is the smallest number that both denominators divide into evenly. For 1/4 and 1/6 it is 12. Using it keeps numbers small when you add or subtract fractions.