First fraction
Second fraction
Fraction arithmetic is straightforward in principle but easy to get wrong under time pressure, especially with mixed numbers or when simplifying the result. This calculator handles the full working — converting mixed numbers, finding common denominators, and reducing the answer.
Every fraction (including a mixed number like 1½) is first converted to an improper fraction — a single numerator over a single denominator. Adding and subtracting need a common denominator, found by multiplying the two denominators together. Multiplying just multiplies numerators and denominators straight across. Dividing multiplies by the reciprocal of the second fraction (flip it, then multiply). The result is then simplified by dividing both numerator and denominator by their greatest common divisor.
The "Whole" field lets you enter a mixed number like 1½ (whole = 1, numerator = 1, denominator = 2) instead of converting it to an improper fraction (3/2) yourself. A negative mixed number applies its sign to the whole part — enter −1 in the Whole field with a positive numerator to mean −1½, not "−1 plus a positive half."
A fraction is fully simplified (in "lowest terms") when its numerator and denominator share no common factor other than 1. This calculator always reduces the result automatically using the greatest common divisor, and also shows the equivalent decimal value for a quick sanity check.