Fraction Calculator
Add, subtract, multiply or divide fractions and mixed numbers. Enter values like 3/4 or 2 1/3.
How to use this calculator
Enter your first value, choose an operation, and enter your second value. You can type a simple fraction like 3/4, a whole number like 5, or a mixed number like 2 1/3 (whole number, a space, then the fraction). Press Calculate and the tool returns the answer reduced to lowest terms, the equivalent decimal, and — when the result is bigger than one — the matching mixed number. It handles addition, subtraction, multiplication and division of fractions and mixed numbers in one place.
The formula explained
Every fraction is a numerator over a denominator. The four operations follow fixed rules:
a/b + c/d = (a·d + c·b) / (b·d)
To add or subtract, the fractions are put over a common denominator (the product of the two denominators works every time), the numerators are combined, and the result is simplified. To multiply, you multiply the numerators together and the denominators together. To divide, you flip the second fraction and multiply. Mixed numbers are first converted into "improper" fractions — a single numerator over a single denominator — so the same rules apply. Finally the answer is reduced by dividing the numerator and denominator by their greatest common divisor.
A worked example
Take 2 1/3 + 1/6. First convert the mixed number: 2 1/3 becomes 7/3. A common denominator for 3 and 6 is 6, so 7/3 becomes 14/6. Now add: 14/6 + 1/6 = 15/6. Simplify by dividing top and bottom by 3 to get 5/2, which as a mixed number is 2 1/2 and as a decimal is 2.5. The calculator shows each of these forms so you can use whichever your work needs.
Frequently asked questions
How do you add fractions with different denominators?
Put both fractions over a common denominator, rewrite each numerator to match, add the numerators, then reduce the result to lowest terms.
How do I enter a mixed number?
Type the whole number, a space, then the fraction. For example, 2 1/3 is read as two and one third.
Does it simplify the answer?
Yes — results are reduced to lowest terms and also shown as a decimal and, where the value exceeds one, as a mixed number.