Math & Everyday Calculators

Proportion Calculator

Use Proportion Calculator free in your browser. No account required; your input is processed locally in your browser.

Runs locallyYour inputs stay in your browser.
Workspace
Result
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HOW IT IS CALCULATED

Solve a missing value in a proportion

Solve equations in the form a/b = c/x using cross multiplication.

Instant resultClear formulaRuns locally
01Values
02x = b × c ÷ a
03Result

2/3 = 4/x → x = 6

GOOD TO KNOW

Cross multiplication removes the denominators

From a/b = c/x you can derive a × x = b × c.

02

In short

What logic does the calculator use?

x = b × c ÷ a

Example?

2/3 = 4/x → x = 6