Coefficient of Variation Calculator
Calculate the relative variability (dispersion) of your data, expressed as a percentage.
What is Coefficient of Variation?
The coefficient of variation (CV) is a standardized measure of dispersion that expresses the standard deviation as a percentage of the mean. It's particularly useful when comparing the variability of datasets with different units or vastly different means.
Formula
CV = (σ / μ) × 100%
Where σ = standard deviation and μ = mean
Interpretation Guidelines
- CV < 15%: Low variability - data points are relatively consistent
- CV 15-30%: Moderate variability - reasonable dispersion around the mean
- CV > 30%: High variability - data points are widely spread
Common Use Cases
- Comparing consistency: Compare variability across datasets with different units (e.g., height in cm vs weight in kg)
- Quality control: Assess the reliability and consistency of manufacturing processes
- Investment analysis: Compare risk relative to expected return across different investments
- Method comparison: Evaluate which measurement technique produces more consistent results
- Assessing reliability: Determine if measurement instruments produce consistent readings
When to Use
Use the coefficient of variation when you want to compare variability across:
- Datasets with different measurement units
- Variables with vastly different means
- Multiple groups or conditions
Note: CV is only meaningful for ratio-scale data (where zero indicates absence of the quantity). It should not be used with interval data (like temperature in Celsius) or when the mean is close to zero.
