Excel STDEV.P Function (Population Spread) – Examples & Practice
Practice the Excel STDEV.P function online with an interactive grid, instant feedback, and clear formula help.
Instruction
Calculate population standard deviation for values in B2:B6.
Formula Syntax
=STDEV.P(number1, [number2], ...)
- number1: First number or range in the population.
- [number2], ...: Optional additional numbers or ranges.
What it does
STDEV.P calculates the standard deviation assuming your data is the complete population. It measures how widely values disperse around the mean.
Excel STDEV.P Function Examples
Spread of a full cohort
=STDEV.P(B2:B6)
Measures dispersion when B2:B6 is the entire population of interest.
Multiple ranges
=STDEV.P(B2:B6, D2:D6)
Combines two groups into one population calculation when that assumption is valid.
With literal numbers
=STDEV.P(2, 4, 9)
Quick check on a tiny set of constants.
statistics-sample.xlsx
| A | B | |
|---|---|---|
| 1 | Sample | Value |
| 2 | S1 | 12 |
| 3 | S2 | 15 |
| 4 | S3 | 15 |
| 5 | S4 | 18 |
| 6 | S5 | 21 |
| 7 | Output |
Input Formula
Need Help?
Tips
- Document whether rows are a population or a sample.
- Plot the series alongside the number to see outliers.
- Compare with [MEDIAN](/excel-practice/median) for skew intuition.
STDEV.P Function Use Cases
- Quality metrics when all production lines are included
- Sports analytics on a closed season dataset
- Benchmarking variance after data cleaning
- Teaching population vs sample concepts
- Pair with AVERAGE for coefficient of variation style thinking
Common mistakes - STDEV.P function not working
- Using STDEV.P on a random sample from a larger universe (use STDEV.S)
- Leaving text in the range
- Confusing standard deviation with standard error
- Single-column mistakes after insert/delete columns
- Tiny sample sizes where SD is unstable
FAQ
STDEV.P vs STDEV.S?
STDEV.P treats data as the full population. STDEV.S applies the sample (n−1) denominator for an estimate from a sample.
When should I use STDEV.P?
When the listed values truly are the entire population you care about (all machines in a plant, all days in a fiscal year).
Does STDEV.P ignore blanks?
Blank cells are ignored; text may cause errors depending on version—keep inputs numeric.
Is this the same as legacy STDEVP?
STDEV.P is the modern name for the population standard deviation function in current Excel.
Does one outlier dominate?
Standard deviation is sensitive to outliers—pair with charts or IQR thinking for skewed data.
Comparison
| Function | Denominator concept |
|---|---|
| STDEV.P | Population |
| STDEV.S | Sample |
| VAR.P / VAR.S | Variance counterparts |
Example
=STDEV.P(B2:B6)=STDEV.S(B2:B6)
Advanced examples
Coefficient of variation (conceptual)
=STDEV.P(B2:B6)/AVERAGE(B2:B6) expresses relative spread—document when averages are near zero.
Rolling stability
Compare STDEV.P over a window vs long-run STDEV.P to detect regime changes (use bounded ranges).