Simplify Ratio Calculator
Simplify ratios, solve proportions A : B = C : x, scale ratios by any factor and convert them to fractions, decimals and percentages — with every step shown.
Processed entirely in your browser — nothing you enter here is ever uploaded.
Result
About this tool
This page opens the ratio calculator in simplify mode: enter the two sides of your ratio and run it to reduce them to lowest terms. The calculator finds the greatest common divisor of both numbers with the Euclidean algorithm and divides it out, so 25 : 10 becomes 5 : 2 and 48 : 180 becomes 4 : 15.
Decimal inputs are handled exactly: 2.5 : 1 is first multiplied by 10 into 25 : 10 and only then simplified to 5 : 2 — no floating-point rounding is involved at any point. Every transformation is listed as a separate step, which makes the tool as useful for checking homework as for quick everyday math.
Simplified ratios appear everywhere: recipes cut down to fewer servings, gear ratios, image shapes, model scales and financial comparisons. The result card also shows the decimal value of the simplified ratio, so two different ratios are easy to compare at a glance.
Example. Simplifying 8:12 yields the reduced integer ratio 2:3.
Limit. Inputs longer than 12 digits are refused, and reduction is exact integer arithmetic after the decimal is scaled away.