Type the top and bottom of each fraction, and a whole part too if it is a mixed number such as 2 1/2. The calculator finds a common denominator with the lcm when it adds or subtracts, inverts the second fraction when it divides, and simplifies the result by the gcd.
Fraction calculator
Enter two fractions or mixed numbers, choose an operation, and see the answer as a simplified fraction, a mixed number and a decimal, with every step written out.
Type a whole part as well to enter a mixed number such as 2 1/2. Use a minus sign for a negative fraction. Whole numbers only, up to 15 digits each.
Try:
Result
1/2 + 1/3 = 5/6
- Simplified fraction
- 5/6
- Decimal
- 0.8(3)
The digits in parentheses repeat forever.
The working
- The denominators are 2 and 3. Their lcm is 6, so 6 is the common denominator.
- Rewrite both fractions over 6: 1/2 = 3/6 and 1/3 = 2/6.
- Add the numerators and keep the denominator: 3/6 + 2/6 = 5/6.
- gcd(5, 6) = 1, so 5/6 cannot be simplified further.
Last reviewed October 19, 2026 ·How pages are reviewed
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