calculators
Rule of Three Calculator
Solve proportional relationships using the rule of three. A is to B as C is to X.
Frequently Asked Questions
How does the rule of three work?
If A/B = C/X, then X = (B × C) / A. This tool calculates X for you.
Can I use it for any proportional relationship?
Yes, for direct proportions where A/B = C/X.
Is my data sent to servers?
No. All calculations happen locally in your browser.