Most fraction tools only add, which leaves you stranded the moment a problem asks for both operations on the same pair of fractions — a recipe you are scaling up in one step and trimming in another, or a homework set mixing plus and minus signs. This calculator handles the pair together. Enter the first fraction in Numerator 1 and Denominator 1, the second in Numerator 2 and Denominator 2, and you get both the Sum and the Difference in one pass. For 1/2 and 1/3, the sum is 5/6 and the difference is 1/6, since 3/6 + 2/6 and 3/6 - 2/6 share the common denominator 6. The same least-common-denominator machinery drives both answers, so seeing them side by side reinforces how addition and subtraction are mirror images. A handy check: add your Sum and Difference results together and you should get exactly twice the first fraction — 5/6 + 1/6 = 1, which is 2 times 1/2. If that check fails, one of the denominators was probably mistyped.

With the pre-filled defaults — Numerator 1 1, Denominator 1 2, Numerator 2 1, Denominator 2 3 — the Adding Subtracting Fractions Calculator returns Sum 0.8333, Difference 0.1667. Change any input and those results update instantly, so you can see exactly how each number you enter moves the answer.