Ratio and Proportion Calculator
Reduce a ratio to its simplest form, or find x in a : b = c : x.
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How to do it
- 1Add the text
Paste or type the text or amount here.
- 2See the result
The result appears right away as you type.
- 3Copy it
Copy the result and use it anywhere. Your text goes nowhere.
About this tool
Choose Simplify to reduce a ratio such as 12 : 18 to 2 : 3 and see each part as a percentage. Choose Solve to find the missing number x in a : b = c : x, useful for recipes, maps, scaling and exchange problems.
Frequently asked questions
What is a proportion?
Two ratios that are equal, for example 12 : 18 = 20 : 30.
How is x found?
x = b × c ÷ a.
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