how to find standard deviation in excel

To find standard deviation in Excel , you mainly use one of two built‑in functions depending on whether your data is a sample or the entire population.

Quick scoop

• Use =STDEV.S(range) for a sample of data (most common).

• Use =STDEV.P(range) for the whole population.

Example:
If your numbers are in cells A1:A10, type in another cell:

• =STDEV.S(A1:A10) for sample standard deviation.

• =STDEV.P(A1:A10) for population standard deviation.

Excel will instantly return the standard deviation value.

Step‑by‑step in Excel

1. Enter your data in a column or row (for example, A1:A10).

2. Click an empty cell where you want the result.
3. Type the formula:
   • Sample: =STDEV.S(A1:A10)
   • Population: =STDEV.P(A1:A10)
4. Press Enter ; Excel shows the standard deviation.

You can also insert the function via Formulas → Insert Function (fx) , choose Statistical , then STDEV.S or STDEV.P , and select your range.

When to use S vs P

Case| Function to use| What it assumes
---|---|---
Your data is a sample (subset of a larger group)| STDEV.S| Divides by n−1n-1n−1 (Bessel’s correction). 34
Your data is the entire population| STDEV.P| Divides by nnn (all data points). 38

For most real‑world datasets (e.g., survey responses, test scores from a class), STDEV.S is the safer default.

A tiny “forum‑style” example

Imagine a small sales‑team thread where someone asks:

“I have monthly sales in A2:A13. How do I show how spread out the numbers are?”

A typical reply would be:

Use =STDEV.S(A2:A13) in another cell; that gives you the sample standard deviation of your sales figures.

You can then pair it with =AVERAGE(A2:A13) to see both center and spread in one glance.

Information gathered from public forums or data available on the internet and portrayed here.