How to use this calculator
Enter whole-number numerators and denominators. Negative fractions are supported; any minus sign is moved to the numerator.
Denominators cannot be zero, and division by a zero-valued fraction is undefined. Input limits keep integer arithmetic within the browser’s exact-number range.
The formula
a/b + c/d = (ad + bc)/bd. Subtract with ad − bc. Multiply = ac/bd. Divide = ad/bc. Reduce by the greatest common divisor.
A worked example
1/2 + 1/3 = 3/6 + 2/6 = 5/6, or approximately 0.833333.
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