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Calculator

Ratio Calculator

Your entries are calculated in this browser and are not saved by this tool.

How the Ratio Calculator works

Simplify a ratio and solve a proportional fourth value. Enter the requested values in the tool above, select Calculate, and review both the main result and its breakdown.

Formula used

Integer ratios are simplified by the greatest common divisor. For a:b = c:x, x = b×c÷a.

Worked example

12:18 simplifies to 2:3. If 12:18 = 20:x, then x = 30.

Practical uses

  • Simplify quantities
  • Scale a recipe
  • Solve a proportion

Assumptions and limits

Results depend on the supplied values and displayed rounding. For reproducibility, record the inputs and assumptions used when sharing a result.

Frequently asked questions

Is this calculator free?

Yes. It can be used without creating an account.

Are the values I enter stored?

The calculation runs in your browser. The core tool does not submit your calculator entries to WordPress.

Can I rely on the result for a major decision?

Use it as an educational estimate, verify important inputs, and seek qualified advice when the decision carries financial, medical, tax or legal consequences.