Fraction Calculator
Add, subtract, multiply and divide fractions, with the answer simplified and shown as a mixed number and decimal.
How to add and subtract fractions
Fractions must have the same denominator before you can add or subtract them. Multiply across to get a common denominator, combine the numerators, then simplify.
a/b + c/d = (a×d + c×b) ÷ (b×d)
3/4 + 5/6 = (18 + 20) / 24 = 38/24. Both numbers divide by 2, so the answer is 19/12, or 1 7/12 as a mixed number (1.5833…).
Multiplying and dividing
To multiply, multiply the tops and multiply the bottoms: 2/3 × 3/5 = 6/15 = 2/5. To divide, flip the second fraction and multiply: 2/3 ÷ 4/5 = 2/3 × 5/4 = 10/12 = 5/6.
Simplifying fractions
Divide the numerator and denominator by their greatest common factor (GCF). For 38/24 the GCF is 2. The calculator finds the GCF with Euclid's algorithm, the same method described in the GCF and LCM calculator.
Improper fractions and mixed numbers
An improper fraction has a numerator larger than its denominator, such as 19/12. To convert it to a mixed number, divide: 19 ÷ 12 = 1 remainder 7, so 19/12 = 1 7/12. To go back, multiply the whole number by the denominator and add the numerator: 1 × 12 + 7 = 19.
Frequently asked questions
How do you add fractions with different denominators?
Find a common denominator, convert both fractions to it, add the numerators and simplify. The calculator does all of this automatically.
How do you divide fractions?
Multiply the first fraction by the reciprocal of the second. For example, 1/2 ÷ 3/4 = 1/2 × 4/3 = 4/6 = 2/3.
How do I enter a mixed number?
Convert it to an improper fraction first. For 2 1/3, multiply 2 × 3 and add 1 to get 7/3.
Last reviewed Oct 20, 2026. Results are estimates; check important decisions with a qualified professional.