How to calculate the coefficient of variation in Excel
Formula (Excel and Google Sheets)
=STDEV.S(B2:B7)/AVERAGE(B2:B7)Divide the standard deviation by the mean and format as a percentage: =STDEV.S(B2:B7)/AVERAGE(B2:B7).
- Result on the example
- 11.1% in
E1 - Works in
- Excel 2010 and later
- Google Sheets
- Same formula
See it work
The formula is already in E1. Change any input and the result updates, or edit the formula to experiment.
How it works
The standard deviation (about 14.5 units) only means something next to the size of the numbers. Dividing by the mean (130) turns it into a relative spread: 11.1%. That lets you compare how steady two products are even when one sells ten times more.
=STDEV.S(B2:B7)/AVERAGE(B2:B7)Result0.1114721288
B2:B76 rows × 1 col: 120, 135, 110, 150, …A range: 6 cells in one column.
STDEV.S(B2:B7)14.49137675STDEV: Sample standard deviation (same as STDEV.S).- number1
B2:B76 rows × 1 col: 120, 135, 110, 150, …
- number1
AVERAGE(B2:B7)130AVERAGE: Arithmetic mean of the numbers.- number1
B2:B76 rows × 1 col: 120, 135, 110, 150, …
- number1
STDEV.S(B2:B7)/AVERAGE(B2:B7)0.1114721288The / operator divides.
In Google Sheets
The same formula works in Google Sheets: =STDEV.S(B2:B7)/AVERAGE(B2:B7). We ran it in Google Sheets mode on the same data and it returns 11.1%.
Other ways to do it
Each one was run on the same example sheet.
| Formula | Result | When to use it |
|---|---|---|
| =STDEV.P(B2:B7)/AVERAGE(B2:B7) | 10.2%Different result | Use the population standard deviation when the weeks are all the data there is. Slightly lower: 10.2%. |
Common mistakes
- The coefficient of variation is meaningless when the mean is near zero or the data has negative values, like temperatures in Celsius.
- Format the cell as a percentage; otherwise it shows 0.11.
Try it yourself
Same data, empty answer cell. Your formula is graded instantly, then re-checked on changed data, so a typed-in number won't pass.
Calculate the coefficient of variation
E1, calculate the coefficient of variation of the weekly units (standard deviation as a share of the mean).Questions
Is there a CV function in Excel?
No; the formula above is the standard way.
What counts as a high CV?
It depends on the field, but under 10% is usually considered steady and over 30% quite variable.
Checked by running on 2026-10-30: every formula and result on this page was calculated by the Spreadsheet Practice formula engine, in both Excel and Google Sheets modes.