Free online calculator

Ratio Calculator

Simplify, scale and compare ratios or solve a missing value in proportional ratios. The calculator supports whole numbers and decimals.

Calculate ratios

How to use the Ratio Calculator

  1. Choose whether you want to simplify, scale, compare or solve a ratio.
  2. Enter the known ratio values.
  3. The calculator reduces or evaluates the ratio using equivalent fractions and greatest common factors where appropriate.
  4. The result includes the simplified or solved ratio and calculation details.

Examples

Simplify a ratio

12:18 simplifies to 2:3 by dividing both values by 6.

Scale a ratio

Scaling 2:3 by 4 gives 8:12.

Solve a missing value

If 2:3 = 8:x, then x = 12.

Frequently asked questions

How do you simplify a ratio?

Convert the ratio terms to whole numbers if necessary, then divide all terms by their greatest common factor.

What are equivalent ratios?

Equivalent ratios describe the same relationship even when the terms are different, such as 2:3 and 4:6.

Can ratios contain decimals?

Yes. Decimal ratios can be converted to whole-number equivalents before simplification.

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