Ratio Calculator
Simplify an A:B ratio to its lowest terms, or solve a proportion A:B = C:? for the unknown. Everything runs in your browser.
Enter values
FAQ
How does simplifying work?
It divides A and B by their greatest common divisor for the simplest integer ratio. Example: 10:15 → 2:3.
How is a proportion solved?
For A:B = C:?, the unknown is B × C ÷ A. Example: 2:3 = 10:? → 15.
Is my input sent to a server?
No. All calculations happen entirely in your browser.
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