Ratio Calculator

The Ratio Calculator simplifies a two-number ratio or solves one missing value in a proportion A:B = C:D.

How it works

For two values A and B, the calculator divides both by their greatest common divisor. With three known values, it rearranges the proportion using cross multiplication.

$\frac{A}{B}=\frac{C}{D}\Rightarrow A\times D=B\times C$

Example

The ratio 24:36 simplifies by their GCD of 12 to 2:3. If 2:3 = 8:D, then D = (3 x 8) / 2 = 12.

Questions

Can ratios contain decimals?

The module accepts finite numeric values, but simplification rounds values when finding the GCD. Use matching units and whole-number values when exact integer simplification matters.

What happens with a zero denominator?

The calculator returns an error rather than dividing by zero.

Can I enter all four values?

Yes. Four values are returned as entered; three values solve the missing proportion value.

Limitations

This is a numeric ratio utility. It does not convert units, interpret rates, or infer which value should be the reference denominator.