Everyday tool

Ratio Calculator

Simplify ratios, scale ratios up or down, and solve missing ratio values.

Start tool ← Back to home View everyday maths cluster

Instant useNo sign up, quick result.

Practical outputBuilt for real everyday checks.

Clear next stepJump from result to related guides.

What this tool helps with

Use this ratio calculator to simplify ratios, compare values and scale recipes, plans or quantities.

Quick start

Enter your values, review the result and use the guide block below for a clearer explanation, example and related tools.

1) Simplify a ratio

First value

Second value

Simplified ratio

2:3

2) Solve a missing ratio value

Known value matching A

Missing value matching B

Calculated value

Quick examples

Question

Input

Result

Simplify 12:18

12 and 18

2:3

3:4 scaled from 15

3, 4, 15

5:8 scaled from 10

5, 8, 10

FAQ

How do you simplify a ratio?

Divide both numbers by their greatest common divisor.

How do you solve an equivalent ratio?

Find the scale factor from the known part, then multiply the matching part by the same factor.

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Guide

How ratio calculations work

Ratios compare one quantity to another. A ratio calculator can simplify values, scale them up or down and help solve equivalent ratios.

This is useful for recipes, finance, classrooms, maps and everyday proportional thinking.

Example

Example use case

A ratio of 8:12 can be simplified by dividing both sides by 4 to get 2:3. The calculator handles that reduction automatically.

Frequently asked questions

What is an equivalent ratio?

Equivalent ratios show the same relationship using different-sized numbers.

Can I scale a ratio?

Yes. Multiplying or dividing both sides by the same number creates another equivalent ratio.

What is this useful for?

It is useful for recipes, school maths, resizing, mixing and comparisons.

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Explore related tools

Use the related tools below to compare scenarios, check supporting numbers or solve nearby tasks faster.

Tool guide

How to use the ratio calculator

Simplify ratios, scale ratios and solve missing values with a free online ratio calculator. Use this page for a fast estimate, compare a few scenarios, and adjust the inputs until the result matches what you need to decide.

This tool also sits inside the CalcBeacon everyday maths and time cluster. That makes it easier to find from category pages, related tools, and supporting guides when you want to compare options.

When it is usefulUse this tool when you want a fast estimate, want to compare options, or want a clearer answer before moving on.

Common mistakesCheck that your numbers use the same units, avoid leaving key fields blank, and test a second scenario so you can see how sensitive the final result is.

Next useful stepAfter using this page, compare the result with a related calculator or open the guide to check the number in context.

Related tools

Use these related tools to compare nearby calculations and move to the next step faster.