Ratio Calculator
Enter a ratio A to B to simplify it to lowest terms, and optionally scale it to find an equivalent ratio.
What this calculator does
A ratio compares two quantities, written as A : B. This calculator reduces any ratio to its lowest (simplest) whole-number terms and can also scale the ratio so you can find an equivalent value when one side changes.
How it works
To simplify a ratio, the calculator finds the greatest common factor (GCF) of A and B and divides both sides by it, the same idea used to reduce a fraction to lowest terms. To scale a ratio, it uses the fact that A : B is equivalent to (A × k) : (B × k) for any scaling factor k, so if you tell it the new value for A, it solves for the matching value of B.
Good to know
Decimal values are supported and handled internally as fractions before simplifying. This tool is intended for general educational and everyday planning purposes, such as scaling a recipe or a mixing ratio.