Fraction calculator to add, subtract, multiply or divide two fractions. Get an exact simplified fraction, a mixed number when it applies and the decimal value.

What is the Fraction Calculator?

The Toolnest Fraction Calculator performs the four basic operations on two fractions and gives an exact, simplified answer. Enter the numerator and denominator of each fraction, choose Add, Subtract, Multiply or Divide, and the result appears in lowest terms along with its mixed-number form (when the answer is larger than one whole) and its decimal equivalent. It is a reliable helper for school homework, recipe scaling and measurement work.

Behind the scenes it uses whole-number arithmetic, so 1/3 stays exactly 1/3 instead of turning into a rounded decimal halfway through. The answer is reduced by the greatest common divisor, and any negative sign is placed on the numerator. Students checking textbook sums, parents helping with maths, and carpenters or cooks working in fractional units will find it quick and dependable.

How to use the Fraction Calculator

Enter the top number of the first fraction in First numerator and the bottom number in First denominator.
Choose Add, Subtract, Multiply or Divide from the Operation menu.
Enter the second fraction in Second numerator and Second denominator.
Press Calculate to see the simplified fraction and, below it, the mixed number (when applicable) and the decimal value.
Copy the answer or press Reset to try another pair of fractions.

Features

Add, subtract, multiply and divide two fractions
Result automatically reduced to lowest terms
Mixed number and decimal equivalent shown alongside the fraction
Exact integer arithmetic for terms up to 10,000,000
Blocks division by a zero fraction with a clear message

Why use this fraction calculator

Check homework answers in seconds
No more hunting for the lowest common denominator
See both fraction and decimal forms at once
Free, ad-hoc use in any browser

Formula used

Addition: (a×d + c×b)/(b×d); reduce numerator and denominator by their gcd. Other operations use standard fraction rules.

Examples

Subtract fractions with different denominators

Input: 3/4 Subtract 1/6

Result: 7/12 Decimal: 0.5833 Three quarters minus one sixth leaves seven twelfths.

Divide one fraction by another

Input: 2/3 Divide 4/9

Result: 3/2 Mixed number: 1 1/2 Decimal: 1.5 Two thirds divided by four ninths is one and a half.

Multiply with a negative fraction

Input: 5/8 Multiply -2/5

Result: -1/4 Decimal: -0.25 The product simplifies to minus one quarter.

Results are estimates for general information, not financial, medical, legal, tax, or property advice. Confirm important figures with the relevant institution or a qualified professional.

Fraction Calculator: frequently asked questions

How do you add fractions with different denominators?

Cross-multiply to get a common denominator: a/b + c/d = (a×d + c×b) ÷ (b×d), then simplify. For 1/2 + 1/3 that gives (3 + 2) ÷ 6 = 5/6. The calculator does this for you and reduces the result by the greatest common divisor, so you always see the answer in lowest terms.

Does the calculator simplify the answer?

Yes. Every result is divided through by the greatest common divisor of its numerator and denominator, so 4/8 + 0/3 appears as 1/2. If the answer is negative, the minus sign is shown on the numerator, for example -1/4. The decimal line underneath gives the same value rounded to up to 4 decimal places, such as 0.5833 for 7/12.

Can I enter mixed numbers like 1 1/2 or decimals?

Not directly. Each numerator and denominator must be a whole number, so a decimal such as 1.5 is rejected. Convert a mixed number to an improper fraction first: 1 1/2 becomes 3/2. The answer is shown as an improper fraction such as 3/2, and when it is larger than one whole the details also show the mixed number, here 1 1/2.

Can a denominator be negative or zero?

No. Denominators must be positive whole numbers from 1 to 10,000,000. To enter a negative fraction, put the minus sign on the numerator instead, such as -2 over 5. Numerators can be anywhere from -10,000,000 to 10,000,000, and zero is allowed except as the second fraction in a division.

How do you divide one fraction by another?

Multiply the first fraction by the reciprocal of the second: (a/b) ÷ (c/d) = (a×d) ÷ (b×c). So 2/3 ÷ 4/9 = 18/12, which simplifies to 3/2. Choose Divide in the Operation menu and the calculator handles the flip and the simplification. Dividing by a fraction whose numerator is zero is not allowed.