Math

Ratio Calculator

Simplify a ratio of two whole numbers to lowest terms.

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Ratio Calculator

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Fractions, Ratios & Proportions

Fraction arithmetic, decimal-to-fraction conversion, ratios and proportions.

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How to use this ratio calculator

Enter the requested values above and select Calculate. The result updates immediately on the page, so you can change one value and compare different scenarios without leaving the calculator.

Formula and method

Divide both terms by their greatest common divisor.

Example

24:36 simplifies to 2:3 because the greatest common divisor is 12.

What this calculator is useful for

Simplify a ratio of two whole numbers to lowest terms. It is designed for quick estimates and everyday problem solving. When a calculation affects a contract, tax filing, medical decision or other high-stakes situation, verify the result with the appropriate professional or authoritative source.

Reduce two quantities to a simple ratio

A recipe uses 24 cups of ingredient A and 36 cups of ingredient B. Divide both numbers by their greatest common factor, 12, to get the ratio 2:3. The units must be comparable if you want the ratio to represent a direct quantity comparison.

Important: 2:3 does not mean 2/5 of the second ingredient. Out of the combined five parts, the first ingredient is 2/5 and the second is 3/5. Reduce the pair before scaling a recipe.

Frequently asked questions

What does the Ratio Calculator calculate?

Simplify a ratio of two whole numbers to lowest terms.

How does the calculation work?

Divide both terms by their greatest common divisor.

Is this calculator free?

Yes. ERICH Calculators is free to use and no account is required.

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Method, assumptions & corrections

See how formulas, sources and limitations are handled across ERICH Calculators.