Ratio Calculator
Calculate and simplify ratios
What is Ratio Calculator?
Ratio Calculator is a free online tool that calculates and simplifies ratios. It can solve for missing values in proportions, simplify ratios to their lowest terms, and scale ratios up or down. Ratios are fundamental in cooking recipes, design proportions, financial analysis, map scales, and scientific measurements. Enter two or more values and the calculator instantly finds the simplified ratio, equivalent ratios, and missing values. All calculations happen in your browser with no data sent to any server.
How to Use
- Enter ratio A and B (e.g. 3:4).
- Enter a value for A or B, and the other is calculated.
Tips & Best Practices
- Use this to scale recipes up or down while maintaining ingredient proportions.
- Simplify ratios by entering large numbers to find the smallest equivalent ratio.
- Use proportion solving to find unknown values in design or engineering calculations.
- Check aspect ratios for images and videos (e.g., 16:9, 4:3) when resizing media.
- Use ratio calculations for dilution ratios in cleaning products and chemical solutions.
Use Cases
Cooking
Scale recipes proportionally when cooking for more or fewer people.
Design
Calculate aspect ratios for images, screens, and print layouts.
Finance
Analyze financial ratios like debt-to-equity, price-to-earnings, and current ratios.
Science
Calculate dilution ratios, mixing proportions, and concentration ratios.
FAQ
How do I use the ratio calculator?
Enter an A:B ratio and one value, and the other value is calculated automatically. The simplified ratio is also shown.
What is a simplified ratio?
It is the ratio reduced to its simplest form by dividing both numbers by their GCD. Example: 4:6 = 2:3
What mathematical principle does ratio calculation use?
It uses the cross-multiplication property of proportions (A:B = C:D means A x D = B x C) to solve for the unknown value.
Is my data sent to any server?
No, all ratio calculations are performed locally in your browser and no data is transmitted externally.
Where can ratio calculation be applied?
It can be applied in many real-life scenarios such as adjusting recipe ingredient ratios, map scale calculations, maintaining image aspect ratios, and material mixing.
Can I calculate ratios with decimal numbers?
Yes, ratios with decimal numbers are calculated accurately, and the simplified ratio is displayed in whole number form.
What is a ratio?
A ratio shows the relative relationship between two or more quantities, expressed as a:b or a/b.
Is my data collected?
No, all calculations happen in your browser. No data is sent to any server.
How do I simplify a ratio?
Divide both numbers by their greatest common divisor (GCD). For example, 12:8 simplifies to 3:2.
Can I solve for missing values?
Yes, enter three values of a proportion and the calculator will find the fourth.
What are equivalent ratios?
Equivalent ratios have the same proportional relationship. 2:3, 4:6, and 6:9 are all equivalent.
How do I scale a ratio?
Multiply both sides by the same number. To scale 1:3 to a total of 20, find 1+3=4, then 20/4=5, giving 5:15.
What is an aspect ratio?
An aspect ratio is the width-to-height ratio of an image or screen, like 16:9 for widescreen or 4:3 for standard.
Can I work with ratios of three or more numbers?
The basic ratio calculation works with two numbers. For three or more, simplify each pair independently.