Choose an operation and enter two fractions to calculate the simplified result.

How to Use the Fraction Calculator

Pick an operation — add, subtract, multiply, or divide — then enter two fractions; switching operations keeps both fractions in place so results are easy to compare across all four.

Addition and subtraction need a common denominator. Multiplication and division don't — and that difference trips people up more than any single formula here.

Add:      a/b + c/d = (ad + bc) / bd
Subtract: a/b − c/d = (ad − bc) / bd
Multiply: a/b × c/d = (a × c) / (b × d)
Divide:   a/b ÷ c/d = (a × d) / (b × c)

Multiplying fractions is just straight across, numerator times numerator, denominator times denominator — it's answering "what fraction of a fraction," not combining like-sized pieces the way addition does, so there's no denominator-matching step needed. Division borrows that same trick after flipping the second fraction upside down, because dividing by a number and multiplying by its reciprocal are always identical (true for whole numbers too — dividing by 2 is the same as multiplying by 1/2).

This Fraction Calculator runs all four operations and simplifies the result to lowest terms.