StatisticsCALCULATOR LAB
DESCRIPTIVE STATISTICS

Coefficient of Variation Calculator

Use a dataset or enter a mean and standard deviation directly to calculate the coefficient of variation as a percentage and compare relative spread.

01 / YOUR INPUTSCalculated in your browser

Enter data or summary values

Try an example:
Enter your observations and choose whether the standard deviation should use the sample or population formula.
Separate values with commas, spaces, tabs or line breaks. You can also paste a column from a spreadsheet.Tip: 10:3 means the value 10 repeated 3 times. Maximum 10,000 values.
Choose sample if your data represent part of a larger group, or population if they include the entire group you want to describe.
02 / YOUR RESULT

See relative variability

Enter your values, or try an example.
Your results and calculation will appear here.

How to use this calculator

  1. Choose dataset or mean and standard deviation.
  2. For a dataset, choose sample or population SD; sample needs at least two observations.
  3. Calculate relative spread. Only compare CV values on meaningful ratio scales.
A QUICK WALKTHROUGH

Worked example: measurements

mode: dataset · basis: sample · data: 12.1, 12.4, 12.2, 12.5

Sample coefficient of variation = 1.4843%

The sample standard deviation is 1.4843% of the mean.

Example calculation
  1. n = 4; sum = 49.2; mean = sum / n = 12.3.
  2. Squared-deviation sum Σ(x − mean)² = 0.1.
  3. Population variance = 0.1 / 4 = 0.025; population SD = √variance = 0.1581.
  4. Sample variance = 0.1 / 3 = 0.0333; sample SD = 0.1826.
  5. CV = 100 × 0.1826 / 12.3 = 1.4843%.

Formula & assumptions

CV (%) = 100 × SD / mean; sample CV uses sample SD; population CV uses population SD.

  • Use ratio-scale measurements with a meaningful zero. Do not use Celsius or Fahrenheit temperatures.
  • This tool uses a positive-mean convention: zero and negative means are rejected, and dataset values must be nonnegative.
  • A mean close to zero makes CV sensitive to small changes. CV is not a confidence interval.
  • “Coefficient of variance” is a common search term for coefficient of variation (relative standard deviation).

How to Calculate CV (Relative Standard Deviation)

The coefficient of variation (CV), also called relative standard deviation (RSD), expresses standard deviation relative to the mean as a percentage. For data with a positive, meaningful ratio-scale mean, CV = (standard deviation / mean) × 100%. It helps compare relative variability across datasets measured on different scales.

For example, a dataset with a mean of 80 and a standard deviation of 12 has a coefficient of variation of 15%. A CV of 15% means that the standard deviation is 15% of the mean.

CV (%) = (Standard deviation / Mean) × 100

Sources

Reviewed: October 2026

Common questions

Can I use CV when the mean is zero or negative?

Not with this calculator. It requires a positive mean and nonnegative ratio-scale data. Near-zero means can make the ratio unstable.

Is CV the same as covariance?

No. The coefficient of variation measures relative dispersion within a dataset. Covariance describes how two variables change together. Although both may be abbreviated informally, they are different statistics.

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Use these tools for mathematical information, not as a substitute for checking assumptions. Read our methodology or disclaimer.