Ratio Calculator
Simplify ratios and solve for the missing value A:B = C:? Simplify ratios to lowest terms, find equivalent ratios and solve proportions for a missing value. Free online ratio and proportion calculator.
About the Ratio Calculator
Ratios compare quantities — 16:12 simplifies to 4:3, and scaling recipes, maps and mixtures is proportion-solving. This calculator does both jobs: reduce any ratio (with up to four parts) to its simplest whole-number form, and find the missing term of a proportion like 3:4 = 15:? instantly. Equivalent ratio tables show the scaling at a glance, useful for adjusting ingredient quantities or interpreting scale drawings.
How to use the Ratio Calculator
- Choose Simplify or Solve mode.
- Enter your ratio values.
- Read the simplified or completed ratio.
- Use the equivalent table to scale quantities.
Key features
- Simplify ratios of two, three or four numbers
- Solve proportions for the missing value
- Equivalent ratio table
- Works with decimals — output in whole numbers
How do I simplify a ratio with decimals?
How is a ratio different from a fraction?
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