Ratio Calculator

 What Is a Ratio?

A ratio is a mathematical way to compare two or more values. It shows how many times one quantity fits into another. For example, if you receive half as many cookies as someone else, you’ve experienced a 1:2 ratio—even if you didn’t express it in numbers.

Ratios are commonly written in three formats:

• Using a colon, like 1:2

• As a phrase, like “1 to 2”

• Or as a fraction, like ½

These all describe the same relationship: the second number is how many units you need of the first to make them equal in value. For instance, in the ratio 2:1, the first number (2) is double the second number (1), meaning the first value contains the second twice.

Ratios aren’t limited to just two terms—you can also work with ratios involving three or more values, such as 1:2:3.

Where Are Ratios Used in Real Life?

Ratios are everywhere in daily life, and you likely use them without realizing it. Here are some practical examples:

• Cooking & Baking: Recipes often use ratios to balance ingredients. A recipe calling for a 1:2:3 ratio of butter, sugar, and flour means you’ll need to double each part if you want to bake twice as much.

• Maps & Models: Scaled-down versions of real-world objects rely on ratios to maintain proportion.

• Finance & Odds: Ratios describe risk, rates of return, and betting odds.

• Screens & Videos: Digital screens and video formats use aspect ratios to define dimensions.

Example: Scaling a Recipe with Ratios

If one cake recipe uses a 1:2:3 ratio for butter, sugar, and flour, and you want to bake 5 cakes, just multiply each number by 5:

• 1 × 5 = 5 parts butter

• 2 × 5 = 10 parts sugar

• 3 × 5 = 15 parts flour

This keeps the proportions balanced while scaling the total quantity.

 Common Aspect Ratios and Screen Resolutions

Aspect ratio refers to the width-to-height relationship of a screen or image. It’s used in everything from computer monitors and smartphones to video content and photography. Below is a helpful chart showing typical screen resolutions and their corresponding aspect ratios: