Ratio to Fraction Converter

About this calculator

A ratio written as a:b and a fraction written as a/b express the same relationship between two quantities, just in different notations. This tool converts the ratio to a fraction and then simplifies it by dividing both terms by their greatest common divisor (GCD) — for example, a ratio of 12:18 becomes the fraction 12/18, which reduces to 2/3 once both numbers are divided by their GCD of 6.

Students and teachers use this conversion constantly when moving between ratio and fraction notation in math class, and it comes up in everyday practical contexts too: scaling a recipe, mixing concrete or paint in a fixed proportion, or reading a map scale all rely on the same ratio-to-fraction logic to get a clean, simplified working number.