Fraction Calculator
Add, subtract, multiply or divide two fractions and get the answer reduced to lowest terms, as a decimal and as a mixed number — with the steps shown for your exact fractions, so it teaches the method as well as giving the result.
5/6 = 5/6 = 0.8333
Results are reduced to lowest terms, with the decimal and mixed-number forms. How we calculate →
How to add and subtract fractions
To add or subtract fractions you need a common denominator. Multiply each fraction so both share the same bottom number, add or subtract the top numbers, then simplify. For 1/2 + 1/3, the common denominator is 6: 1/2 becomes 3/6 and 1/3 becomes 2/6, so the sum is 5/6. The calculator above shows each step for the exact fractions you enter — not a generic example.
How to multiply and divide fractions
Multiplying is the easy one: multiply the numerators together and the denominators together, then simplify. 2/3 × 3/4 = 6/12 = 1/2. To divide, flip the second fraction and multiply — 1/2 ÷ 1/4 becomes 1/2 × 4/1 = 4/2 = 2. The calculator handles all four operations and shows the flip-and-multiply step for division.
Simplifying to lowest terms
A fraction is in lowest terms when the top and bottom share no common factor other than 1. To simplify, divide both by their greatest common factor (GCF): 6/8 has a GCF of 2, so it reduces to 3/4. The calculator always reduces the answer automatically and tells you when it did, so you get the cleanest form every time.
Fractions, decimals and mixed numbers
Every fraction is also a decimal — just divide the top by the bottom: 3/4 is 0.75, 1/3 is 0.333…. A fraction larger than 1 (an improper fraction like 7/4) can be written as a mixed number (1 3/4). The calculator shows all three forms of the answer — the reduced fraction, the mixed number and the decimal — so you can use whichever you need.
Working with negative fractions
Negative fractions follow the same rules; the sign just travels with the numerator. −1/2 + 1/4 is −2/4 + 1/4 = −1/4. The calculator keeps the sign on top and in lowest terms, so a result like 2/−4 is shown cleanly as −1/2.
Why a common denominator matters
You can only add quantities that are the same size. Thirds and halves are different-sized pieces, so 1/2 + 1/3 isn't 2/5 — you first re-cut both into sixths so the pieces match. That's the whole reason for the common denominator, and it's the single most common mistake in fraction arithmetic. Seeing the step laid out makes it click.
Frequently asked questions
How do I add fractions?
Give them a common denominator, add the numerators, then simplify. For 1/4 + 1/6, the common denominator is 12: 3/12 + 2/12 = 5/12. The calculator above shows each step for your fractions and reduces the answer automatically.
How do I subtract fractions?
As with addition, use a common denominator and subtract the numerators. 3/4 − 1/6 = 9/12 − 2/12 = 7/12. Enter both fractions above and choose the minus operation to see the working.
How do I multiply fractions?
Multiply the numerators together and the denominators together, then simplify: 2/3 × 4/5 = 8/15. No common denominator is needed for multiplication. The calculator does it instantly.
How do I divide fractions?
Flip the second fraction (the divisor) and multiply: 3/4 ÷ 2/5 = 3/4 × 5/2 = 15/8 = 1 7/8. The calculator shows the flip-and-multiply step and gives the answer as a fraction, mixed number and decimal.
How do I simplify a fraction?
Divide the numerator and denominator by their greatest common factor. 8/12 has a GCF of 4, so it simplifies to 2/3. The calculator always returns the answer in lowest terms and notes when it reduced it.
How do I convert a fraction to a decimal?
Divide the numerator by the denominator: 5/8 = 5 ÷ 8 = 0.625. The calculator shows the decimal form of every result alongside the fraction and mixed-number forms.
What is an improper fraction and a mixed number?
An improper fraction has a numerator larger than its denominator (like 7/4); a mixed number writes that as a whole number plus a fraction (1 3/4). They're equal — the calculator shows both forms of the answer.
Why isn't 1/2 + 1/3 equal to 2/5?
Because you can't add fractions with different denominators directly — halves and thirds are different-sized pieces. You first convert both to sixths (3/6 and 2/6), which add to 5/6. The calculator handles the common denominator for you.
Researched & verified by the Calcuris Data & Research Team. How we build and check our tools →