Ratio Simplifier

About this calculator

This tool reduces a ratio written as a:b to its lowest terms by dividing both numbers by their greatest common divisor, the same way a fraction is simplified, and also expresses the result as a decimal value. A ratio like 15:25 and its simplest form 3:5 describe exactly the same proportional relationship, but the simplified version makes that relationship immediately clear.

Ratios in their simplest form are used across cooking and mixing (concentrate-to-water ratios, recipe scaling), finance (debt-to-income, price-to-earnings and similar ratios that are easier to interpret when reduced), photography and design (aspect ratios like 16:9 or 4:3), and general math and science coursework where simplifying a ratio is a routine step before comparing it to another. Reducing two ratios to their simplest forms is also the quickest way to check whether they're actually equal.