Finance function
Excel STDEV.S function
STDEV.S measures how spread out a set of numbers is, treating them as a sample of a bigger group. A small result means the values sit close to the average. Use it for survey scores, delivery times, or test results.
=STDEV.S(number1, [number2], ...)Arguments
number1- The first number or range of the sample.
number2- Optional. More numbers or ranges to include.
STDEV.S examples
Every result below was calculated live from this sample sheet.
| A | B | C | |
|---|---|---|---|
| 1 | Respondent | Score (1-10) | Wait (min) |
| 2 | R-01 | 8 | 12 |
| 3 | R-02 | 6 | 30 |
| 4 | R-03 | 9 | 8 |
| 5 | R-04 | 7 | 15 |
| 6 | R-05 | 8 | 22 |
| 7 | R-06 | 5 | 10 |
Result: 1.47
Scores vary by about 1.47 points around their average.
Result: 8.35
Wait times are much more spread out, about 8.4 minutes.
Result: 0.52
Divide by the average to compare spread on different scales.
Result: #DIV/0!
A single value has no spread to measure, so you get #DIV/0!.
How to use STDEV.S
- Click the cell for the result.
- Type =STDEV.S(
- Select the numbers.
- Press Enter and round the result if needed.
Common STDEV.S mistakes
Using STDEV.S on a whole population
If you have every value, not a sample, use STDEV.P. It divides by n instead of n-1.
Numbers stored as text in the range
Text in a referenced range is ignored, so the result can be off. Convert those cells to numbers.
Only one value
STDEV.S needs at least two numbers, or it returns #DIV/0!.
STDEV.S FAQ
What is the difference between STDEV.S and STDEV.P in Excel?
STDEV.S is for a sample and divides by n-1. STDEV.P is for the whole population and divides by n, so it gives a slightly smaller answer.
How do I calculate standard deviation in Excel?
Use =STDEV.S(range) for a sample, which is the usual case for survey or test data.
Is STDEV the same as STDEV.S?
Yes. STDEV is the older name and gives the same result. Microsoft recommends STDEV.S in new workbooks.
Practice STDEV.S in these lessons
Related functions
Updated 2026-10-31