Coefficient of Variation Calculator Formula
Understand the math behind the coefficient of variation calculator. Each variable explained with a worked example.
Formulas Used
Coefficient of Variation
cv = (std_dev / abs(mean_val)) * 100CV as Decimal
ratio = std_dev / abs(mean_val)Variables
| Variable | Description | Default |
|---|---|---|
std_dev | Standard Deviation | 5 |
mean_val | Mean | 50 |
How It Works
How to Calculate the Coefficient of Variation
Formula
CV = (Standard Deviation / Mean
The CV is a dimensionless measure of relative variability. It allows comparison of spread across datasets with different units or vastly different means. A CV of 10% means the standard deviation is 10% of the mean.
Worked Example
A dataset has a mean of 50 and standard deviation of 5. Find the CV.
- 01CV = (5 / |50|) * 100%
- 02CV = 0.10 * 100%
- 03CV = 10%
Frequently Asked Questions
When is the coefficient of variation useful?
It is useful for comparing variability between datasets measured in different units (e.g., height in cm vs. weight in kg) or with very different magnitudes.
Can the CV be used when the mean is zero?
No. When the mean is zero, the CV is undefined because you would divide by zero. The CV is also unreliable when the mean is close to zero.
What is considered a high CV?
Context matters, but generally a CV above 30% indicates high variability relative to the mean. In laboratory assays, a CV above 10% may be considered unacceptable.
Ready to run the numbers?
Open Coefficient of Variation Calculator