Coefficient of Variation Calculator
Measure relative variability as the ratio of standard deviation to mean.
Results update as you type.
About this calculator
The coefficient of variation (CV) expresses the standard deviation as a percentage of the mean, giving a unit-free measure of relative spread. Because it is scale-independent, the CV lets you compare the variability of data sets that have very different means or units. This calculator uses the sample or population standard deviation you choose over the mean of the data.
Frequently asked questions
What is a high coefficient of variation?
There is no universal cutoff, but a CV below about 15% is often considered low (consistent) variability and above 30% relatively high. Always judge it against typical values for your field.
When is the coefficient of variation not useful?
The CV is unreliable when the mean is near zero, because dividing by a tiny mean makes it explode, and it is not meaningful for data with negative values or data that lacks a true zero point, such as temperatures in Celsius.
Results are estimates for general guidance only, not financial, medical or tax advice.