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Ratio Calculator
Simplify ratios and solve proportions.
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How to use the Ratio Calculator
- 1Enter your ratio, or three parts of a proportion to solve for the fourth.
- 2Choose to simplify or solve.
- 3Read the simplified ratio or the missing value.
About the Ratio Calculator
Free ratio calculator — simplify a ratio to its lowest terms, scale it up or down, or solve for a missing value in a proportion (A:B = C:D). Instant, accurate results.
Part of our Calculators collection. Browse all tools.
Frequently asked questions
- Can it solve for a missing number?
- Yes — enter A:B = C:? (or any one blank) and the calculator solves the proportion for the missing value.
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