Coefficient of Variation Calculator

Express standard deviation relative to the mean for scale-free comparison.

About Coefficient of Variation Calculator

Because the coefficient of variation is dimensionless, it lets variability be compared across datasets with different units or wildly different magnitudes. It is meaningless when the mean is near zero. Comparing raw standard deviations across datasets with different scales is misleading, which is exactly the problem CV solves.

Formula

Coefficient of Variation

CV = standard deviation ÷ mean × 100

CV: Dimensionless, so datasets in different units can be compared

Worked example

With the default values below, Coefficient of Variation Calculator returns Coefficient of Variation of 18.0000%. Change any input above and every figure here is recalculated in your browser.

Inputs used

Mean: 250
Standard deviationminimum 0: 45
Mean of a second dataset: 12
Standard deviation of the second datasetminimum 0: 3

Results

Coefficient of Variation: 18.0000%
Coefficient of Variation of the Second Dataset: 25.0000%
Which Dataset Is More Variable: The second dataset is relatively more variable
Signal to Noise Ratio: 5.55556
Interpretation: Moderate relative variability

Step by step

1Values used
2Coefficient of Variation
3Coefficient of Variation= 18.0000
4Coefficient of Variation of the Second Dataset= 25.0000
5Which Dataset Is More Variable= The second dataset is relatively more variable
6Signal to Noise Ratio= 5.55556
7Interpretation= Moderate relative variability

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 5 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How is Coefficient of Variation calculated?

CV = standard deviation ÷ mean × 100 Because the coefficient of variation is dimensionless, it lets variability be compared across datasets with different units or wildly different magnitudes. It is meaningless when the mean is near zero.

Why does Coefficient of Variation matter?

Comparing raw standard deviations across datasets with different scales is misleading, which is exactly the problem CV solves.

What values do I need to enter?

This calculator takes 4 inputs: Mean, Standard deviation, Mean of a second dataset, Standard deviation of the second dataset. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.