Type a fraction question and this calculator works out the answer. The tool takes two proper or improper fractions, each entered as a whole-number numerator over a denominator, and adds, subtracts, multiplies, or divides them. The stacked numerator-over-denominator entry used here matches the pattern of the ranking fraction calculators on the web, so you can tell the tool exactly what to compute by picking one of the four operator buttons between the two columns.

How to use the fraction calculator

Enter the numerator and denominator of the first fraction on the left, then the numerator and denominator of the second fraction on the right. The numerator field sits above the dividing line and the denominator field below it. A denominator can never be zero, and each value must be a whole number. Choose +, -, *, or / for the operation and press Calculate.

The answer appears reduced to lowest terms. When the result is an improper fraction (a top number larger than the bottom number), the equivalent mixed number is shown next to it, and the decimal value sits underneath. The Copy result button copies the fraction to the clipboard.

Worked examples

1/2 + 1/3 = 5/6. The lowest common denominator of 2 and 3 is 6, so 1/2 becomes 3/6 and 1/3 becomes 2/6, giving 5/6 in lowest terms.
3/4 / 1/6 = 9/2 = 4 1/2. Division flips the second fraction, turning the problem into 3/4 x 6/1 = 18/4, which simplifies to 9/2 or the mixed number 4 1/2.
2/3 x 9/8 = 3/4. Multiply across to get 18/24, then reduce by the greatest common factor 6.

What the result means

The main answer is the simplified fraction, which means the numerator and denominator share no common factor larger than 1. An improper fraction is also written as a whole number plus a proper fraction, for example 9/2 = 4 1/2. The decimal line shows the exact terminating decimal when one exists, or the first recurring digits with an ellipsis for fractions such as 1/3 = 0.333333…

Limits and edge cases

Every input must be an integer between -999999 and 999999; negative numerators are allowed. A zero denominator makes a fraction undefined and is rejected, and so is dividing by a fraction with a numerator of zero. The step-by-step explanation under the result shows the lowest common denominator used for addition and subtraction, the flip step used for division, and the greatest common factor used to simplify the answer.