CalcMate

Fraction Calculator

Work with two fractions at once: add, subtract, multiply or divide them and get the answer as a simplified fraction, a decimal and a mixed number, with every step of the reduction shown.

Result5/4
Decimal1.25
Mixed number1 1/4

The answer is always reduced with the greatest common divisor, so 6/8 is shown as 3/4.

Formula and calculation

Add or subtractab±cd=a×d±c×bb×d, then divide top and bottom by their GCFMultiplyab×cd=a×cb×dDivideab÷cd=a×db×c — flip the second fraction and multiply\begin{gathered}{\footnotesize\text{Add or subtract}}\\ \dfrac{a}{b} \pm \dfrac{c}{d} = \dfrac{a \times d \pm c \times b}{b \times d}, \text{ then divide top and bottom by their GCF}\\[6pt]{\footnotesize\text{Multiply}}\\ \dfrac{a}{b} \times \dfrac{c}{d} = \dfrac{a \times c}{b \times d}\\[6pt]{\footnotesize\text{Divide}}\\ \dfrac{a}{b} \div \dfrac{c}{d} = \dfrac{a \times d}{b \times c}\ \text{— flip the second fraction and multiply}\end{gathered}
Fraction arithmetic as taught in any standard textbook: the result of every operation is reduced by the greatest common divisor (GCF), and the steps table shows the common denominator and the GCF that were used for your numbers.

Worked example

To add 1/2 and 3/4, put both over the common denominator 4: 2/4 + 3/4 = 5/4. The calculator reports 5/4, which is 1.25 as a decimal and 1 1/4 as a mixed number.

Why fractions get reduced

Reducing does not change the value — it changes how the same amount is written. 6/8 and 3/4 cover exactly the same distance on a ruler; reducing just divides the numerator and denominator by their greatest common divisor (2, in this case). Lowest terms make comparison and further arithmetic easier: 3/4 is visibly bigger than 2/3, while 9/12 versus 8/12 takes a moment. The step-by-step table here always shows the GCF that was applied, so you can reproduce the reduction by hand.

Mixed numbers and improper fractions

A mixed number such as 2 1/2 is shorthand for 2 + 1/2, which is 5/2 as an improper fraction (2 × 2 + 1 = 5 over the same denominator 2). To convert back, divide the numerator by the denominator: 5 ÷ 2 is 2 with a remainder of 1, so 1/2. Cooks and carpenters work in mixed numbers; algebra almost always uses improper fractions, because multiplying and dividing mixed numbers directly is where most mistakes happen. This calculator accepts either form and reports both.

What the results mean

Result
The answer as a fraction in lowest terms — the numerator and denominator have no common factor left, so 6/8 is always reported as 3/4.
Decimal
The same answer written as a decimal. It is exact when the fraction ends (1/4 = 0.25) and repeating when it does not (1/3 = 0.3333…).
Mixed number
The answer as a mixed number — a whole number next to a proper fraction, like 1 1/2. This is the form used in recipes and measurements; improper forms like 3/2 are preferred in algebra.

Frequently asked questions

How do I add fractions with different denominators?

Rewrite both fractions with a common denominator, then add only the numerators. For 1/2 + 1/3 the smallest common denominator is 6: 3/6 + 2/6 = 5/6. The steps table shows the least common denominator used for your numbers.

Why isn't 1/2 + 1/3 equal to 2/5?

Because denominators cannot be added — they count how many pieces each whole is cut into, not how much you have. You must first cut both into equal pieces: 3/6 + 2/6, which is 5/6, a little less than 1. Adding 1/2 and 1/3 should land near 0.83, and 2/5 is only 0.4.

How do I turn a mixed number into a fraction?

Multiply the whole number by the denominator and add the numerator, keeping the same denominator. 2 1/2 becomes (2 × 2 + 1)/2 = 5/2. Type mixed numbers straight in, like 2 1/2, and the calculator converts them for you.

What does simplifying a fraction mean?

Dividing the numerator and denominator by their greatest common divisor until nothing is left to cancel. 12/18 becomes 2/3 (both divided by 6). The value never changes — only the way it is written. The calculator always reports the reduced form.