Ratio Calculator
Calculate missing values in a ratio quickly and accurately.
Enter any three values to calculate the fourth in the ratio A : B = C : D.
Ratio Scaling Calculator
Scale a ratio by increasing or shrinking both values by the same factor.
What Is a Ratio?
A ratio is a quantitative relationship between two or more values that compares their relative sizes. Ratios are commonly written using a colon, such as 1 : 2, and can also be expressed as "1 to 2" or as a fraction.
Ratios are used in many everyday applications, including comparing quantities, maps and models, cooking and baking, screen dimensions, and rates.
How Ratio Calculations Work
A ratio can be used to compare two or more values while keeping their relationship consistent. In the ratio A : B = C : D, knowing any three values allows the fourth value to be calculated.
A : B = C : D
The calculator uses the relationship between the known values to determine the missing value.
How Ratio Scaling Works
Ratio scaling means multiplying or dividing both values in a ratio by the same factor. This keeps the relationship between the two values consistent.
250 : 280 ÷ 2.5 = 100 : 112
You can increase a ratio by multiplying both values by the scale factor, or shrink it by dividing both values by the scale factor.
Frequently Asked Questions
What is a ratio?
A ratio compares two or more quantities and shows their relationship to one another.
How many values do I need to enter?
Enter any three values in A : B = C : D and leave the fourth value empty.
Can I use decimal values?
Yes. The calculator accepts decimal values for ratio calculations.
Can I scale a ratio?
Yes. The Ratio Scaling Calculator can increase or shrink both values by the same scale factor.
What happens when I shrink a ratio?
Both values are divided by the selected scale factor while keeping the same relationship between them.
What happens when I increase a ratio?
Both values are multiplied by the selected scale factor while keeping the same relationship between them.
Can I use decimal scale factors?
Yes. The Ratio Scaling Calculator accepts decimal scale factors such as 1.5 or 2.5.
Disclaimer
This calculator is provided for general mathematical and educational purposes. While we aim to provide accurate results, SmartMyTools does not guarantee that the results are suitable for professional, academic, financial, engineering, or other specialized applications.