% Percentage Calculator

Standard Deviation as % of Mean

Sometimes called coefficient of variation (CV). Useful for comparing variability across different scales.

Enter values above to calculate.

CV is unit-free, so you can compare 'how variable' two different metrics are.

Worked examples
Mean 100, SD 5: CV = 5%.
Mean 100, SD 25: CV = 25%.

Frequently asked questions

Is CV always useful?
Less meaningful when mean is near zero.