Ratio Calculator

Simplify ratios, find equivalent ratios, and convert ratios to percentages. Fast, accurate, and easy to use.

Simplify Ratio

Find Equivalent Ratio

If A:B = C:D, find D

Convert Ratio to Percentage

Ratio Formulas

Simplify Ratio

A:B = (A÷GCD):(B÷GCD)

Example: 12:8 = 3:2 (GCD = 4)

Equivalent Ratio

If A:B = C:D, then D = (B×C)÷A

Example: 2:3 = 4:D, D = (3×4)÷2 = 6

Ratio to Percentage

A% = (A÷(A+B))×100

Example: 3:2, A = 60%, B = 40%

How to Use This Calculator

1

Choose Operation

Select the tab for what you want to do: simplify a ratio, find an equivalent ratio, or convert to percentage.

2

Enter Values

Input the numbers for your ratio. For equivalent ratios, enter three known values to find the fourth.

3

Calculate

Click the Calculate button to get your result instantly with a clear explanation.

Example Calculations

Recipe Scaling

A recipe uses flour and sugar in a 3:2 ratio. If you use 9 cups of flour, how much sugar?

Solution: 3:2 = 9:x, x = (2×9)÷3 = 6 cups

Simplify Ratio

Simplify the ratio 24:36

Solution: GCD(24,36) = 12, 24:36 = 2:3

Where Ratios Are Used

Cooking & Recipes

Scale recipes up or down, maintain ingredient proportions, and convert measurements. Essential for baking and meal preparation.

Finance & Business

Calculate financial ratios, profit margins, debt-to-equity ratios, and return on investment. Critical for business analysis and decision-making.

Maps & Scale Models

Understand map scales, create architectural models, and convert between real and model dimensions in design and planning.

Chemistry & Science

Mix solutions with correct concentrations, calculate chemical ratios, and prepare laboratory mixtures with precise proportions.

Photography & Design

Maintain aspect ratios when resizing images, calculate crop dimensions, and ensure proper proportions in graphic design work.

Education & Math

Fundamental concept in mathematics, used in proportions, percentages, and problem-solving. Essential for standardized tests and coursework.

Frequently Asked Questions

What is a ratio?

A ratio is a comparison of two quantities showing how many times one value contains another. It's written as A:B or A/B. For example, 3:2 means for every 3 units of A, there are 2 units of B.

How do you simplify a ratio?

To simplify a ratio, divide both numbers by their greatest common divisor (GCD). For example, 12:8 has a GCD of 4, so 12÷4:8÷4 = 3:2.

What are equivalent ratios?

Equivalent ratios are ratios that express the same relationship. For example, 1:2, 2:4, and 3:6 are all equivalent because they simplify to the same ratio.