Ratio Calculator

What Is a Ratio?

A ratio compares two or more quantities. It shows how much of one quantity there is relative to another. For example, if one group has two objects and another has three, their ratio is 2:3.

Ratios are commonly written with a colon, as words such as “2 to 3,” or as a fraction such as 2/3. The order matters: 2:3 and 3:2 describe different comparisons. Ratios can also contain more than two terms, such as 1:2:3.

Ratios are useful in everyday life, including cooking, mixing ingredients, comparing prices, reading maps, scaling models, and describing screen dimensions. If a recipe uses ingredients in a 1:2:3 ratio, multiplying every term by five gives 5:10:15 while preserving the relationship.

Typical Aspect Ratios and Screen Resolutions

An aspect ratio compares the width of a rectangle with its height. For screens and videos, it is commonly written as width:height. Resolution gives the actual pixel dimensions.

Aspect ratios are rounded to common display conventions where indicated with ~.