Coefficient of Variation Calculator

Compute the coefficient of variation (CV) as the ratio of standard deviation to the mean.

Enter your data set. Invalid values will be ignored.

What the Coefficient of Variation Measures

The coefficient of variation (CV) expresses the standard deviation as a percentage of the mean. It is a standardized, unit-free measure of relative variability, which makes it useful for comparing the dispersion of two or more data sets that have different units or very different means. A lower CV indicates less relative spread around the mean, while a higher CV indicates greater relative spread.

How It Is Calculated

This calculator uses the sample standard deviation (dividing by n − 1) to compute the headline coefficient of variation. The standard deviation is divided by the mean and multiplied by 100 to express the result as a percentage.

  • Mean: xÌ„ = Σxáµ¢ / n
  • Sample standard deviation: s = √(Σ(xáµ¢ − xÌ„)² / (n − 1))
  • Coefficient of variation: CV = (s / xÌ„) × 100%

When to Use the CV

The coefficient of variation is most meaningful for data measured on a ratio scale with a positive mean, such as heights, weights, or prices. It should be used with caution when the mean is close to zero, because small changes in the mean can cause large swings in the CV. The sample version requires at least two values.