Fraction Calculator
Calculate with fractions and mixed numbers and get the answer as a simplified fraction, a mixed number and a decimal.
Result
Enter your values and select Calculate to see the result.
How to use this calculator
- Enter each fraction as a numerator and denominator. For a mixed number such as 2 ¾, also fill in the whole-number box.
- To make a mixed number negative, put the minus sign on the whole number only (−2 ¾ is whole −2, numerator 3, denominator 4).
- Choose the operation. The answer is simplified automatically.
Formula
- Add:
a/b + c/d = (a×d + c×b) ÷ (b×d) - Subtract:
a/b − c/d = (a×d − c×b) ÷ (b×d) - Multiply:
a/b × c/d = (a×c) ÷ (b×d) - Divide:
a/b ÷ c/d = (a×d) ÷ (b×c)
The result is simplified by dividing the numerator and denominator by their greatest common divisor. A mixed number w n/d is first converted to (w×d + n)/d.
Worked example
2/3 + 3/4
(2×4 + 3×3) ÷ (3×4) = 17/12 = 1 5/12 ≈ 1.416667.
1 ½ ÷ ¾
1 ½ = 3/2. Dividing by 3/4 means multiplying by 4/3: 3/2 × 4/3 = 12/6 = 2.
Assumptions and limitations
- Numerators, denominators and whole numbers must be whole numbers.
- A denominator of zero, or dividing by a fraction equal to zero, is reported as an error.
- Decimals are shown to up to 10 places; repeating decimals are marked as repeating.
Frequently asked questions
How do I enter an improper fraction like 7/3?
Leave the whole-number box empty and enter 7 as the numerator and 3 as the denominator. The answer will also show it as the mixed number 2 1/3.
How do I know if a fraction gives a repeating decimal?
A simplified fraction has a terminating decimal only when its denominator has no prime factors other than 2 and 5. So 1/8 = 0.125 terminates, but 1/3 = 0.333… repeats.