In this article
STDEV estimates the standard deviation from a sample. It is a compatibility function: Excel keeps it so workbooks from Excel 2007 and earlier still calculate, but Microsoft recommends STDEV.S for new work. Both give the same result.
Advertisement
Syntax
=STDEV(number1, [number2], ...)| Argument | What it means |
|---|---|
number1… |
Sample values |
Examples
Example 1
=ROUND(STDEV(INDEX({12,15,18,22,25,30,41},SEQUENCE(A2))),3)Result: 3. See the worked example table below for more cases.
💡 For new workbooks use STDEV.S: it gives the same answer and is the name Microsoft keeps documenting.
STDEV in practice
Where you will use it
- Opening and checking older workbooks that use STDEV
- Understanding formulas shared by colleagues on older Excel versions
- Knowing when to swap in STDEV.S for clarity
Worked example
| Rows used | Formula | Result |
|---|---|---|
| 3 | =ROUND(STDEV(INDEX({12,15,18,22,25,30,41},SEQUENCE(A2))),3) | 3 |
| 5 | =ROUND(STDEV(INDEX({12,15,18,22,25,30,41},SEQUENCE(A3))),3) | 5.225 |
| 7 | =ROUND(STDEV(INDEX({12,15,18,22,25,30,41},SEQUENCE(A4))),3) | 9.895 |
Results calculated in Excel. Same result as STDEV.S.
Mistakes people make
| Mistake | What to do instead |
|---|---|
| Using STDEV in new files | Prefer STDEV.S: same result, clearer name, and the function Microsoft keeps improving |
| Mixing old and new names in one model | Pick one style per workbook so formulas are easy to audit |
Related functions
📚 Part of the free Excel course: Beginner → Expert · Try it in the Formula Lab or ask the AI Helper.
✨ Ask AI about this article
Stuck on a step? Ask a question and the AI answers using this article.
Free · AI can be wrong