Add, subtract, multiply, or divide two fractions — the result is automatically simplified to its lowest terms.
Fraction Calculator
LiveResult
5/6
Decimal
0.8333
Result is always shown in lowest terms.
The formulas
Add/Subtract: a/b ± c/d = (ad ± cb) / bd
Multiply: a/b x c/d = ac / bd
Divide: a/b / c/d = ad / bc
Example
1/2 + 1/3 = (1x3 + 1x2) / (2x3) = 5/6 = 5/6 (already in lowest terms).
Step-by-step guide
- Enter the first fraction's numerator and denominator.
- Choose an operation - add, subtract, multiply, or divide.
- Enter the second fraction and read the simplified result and its decimal equivalent.
Common mistakes
Adding numerators and denominators directly (1/2 + 1/3 is not 2/5) - fractions need a common denominator first.
Forgetting to flip the second fraction when dividing - division means multiplying by the reciprocal.
Frequently asked questions
Why is my answer shown in lowest terms?
Simplifying to lowest terms is the standard way to express a fraction answer - it divides both the numerator and denominator by their greatest common factor.
Can I use negative numbers?
Yes - enter a negative numerator or denominator and the calculator handles the sign correctly in the simplified result.
What if my result is a whole number?
If the denominator simplifies to 1, the calculator shows just the whole number instead of an unnecessary "/1".
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