Simplify Ratio Calculator

About this calculator

Simplifying a ratio means reducing both sides to the smallest whole numbers that keep the same proportion — for example, 12:18 simplifies to 2:3. The method is to find the greatest common divisor (GCD) of the two numbers and divide both by it, the same principle used to reduce a fraction to lowest terms.

This calculator finds that simplest form automatically and also shows the equivalent decimal value, so you can read the relationship either way. Simplified ratios come up constantly in everyday and professional contexts: scaling a recipe up or down, mixing paint or cleaning solutions in the right proportion, working out an image or screen's aspect ratio, or presenting a business metric (like a debt-to-equity or student-to-teacher ratio) in its clearest form.