Calculators

Fraction Calculator

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.

  • 100% free
  • No sign-up
  • Private: runs on your device
  • Updated

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Your result

Your result, a full breakdown and charts appear here as you type.

What is 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 Fraction Calculator

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

Key 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.

Fraction Calculator examples

1

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.

2

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.

3

Multiply with a negative fraction

Input: 5/8 Multiply -2/5

Result: -1/4
Decimal: -0.25

The product simplifies to minus one quarter.

Important notes before you rely on the result

  • Enter plain numbers; commas, spaces and currency signs are removed automatically, so 1,50,000 and 150000 give the same answer.
  • Results are rounded for display (up to 4 decimal places) but calculated at full precision, so a hand calculation with rounded steps can differ in the last digit.
  • Use the same unit for every input. Mixing rupees and thousands of rupees, or marks out of 50 and out of 100, gives a wrong answer.

Privacy and data handling

Runs in your browser. Nothing you enter is uploaded or saved.

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.

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.