Summary

STDEV.P returns the standard deviation for a population. Standard deviation measures how far values tend to sit from the average, so it helps describe how tightly or loosely the full dataset is grouped.

The .P means population. Use this version when the dataset already contains every value you want to measure. If your numbers are only a sample from a larger population, use STDEV.S instead.

Syntax

=STDEV.P(number1, [number2], ...)

You can use cell ranges, individual references, typed values, or a mix of them.

Arguments

• number1 - [required] The first number, range, or reference in the population.
• number2, ... - [optional] Additional population values or ranges.

STDEV.P vs Other Functions

Using the STDEV.P Function

STDEV.P is a good fit when the list in front of you is the whole group you care about. If you are measuring all scores from a class, every batch from a day, or the complete monthly dataset, this version matches that situation better than the sample version.

Microsoft notes that STDEV.P assumes the arguments represent the entire population. It also notes that logical values and text representations of numbers typed directly into the argument list are counted, while text and logical values inside references are ignored. Blank cells in references are ignored as well.

Like any standard deviation, the number is easiest to understand in context. A low result means the values stay relatively close to the mean, while a high result means they are more spread out. The result uses the same units as the original data, which often makes it easier to interpret than variance.

Example 1 - Measure spread for a full range

This is the standard pattern when your sheet already contains the full group you want to analyze.

=STDEV.P(B1:B10) // Returns the population standard deviation for the range.

Example 2 - Check a stable set

Values that stay close together give you a smaller standard deviation.

=STDEV.P(10,11,10,9) // Returns a relatively small spread.

Example 3 - Check a wider set

When the values are farther apart, the result becomes larger.

=STDEV.P(10,50,10,90) // Returns a much larger spread.

Example 4 - Use it as a full-population stability check

This works well when you want one number that summarizes how spread out the full dataset is.

=STDEV.P(B1:B10) // Returns the population standard deviation for the range.

Conclusion Recap

• Main job: STDEV.P measures population standard deviation.
• Use it for full populations: Choose it when the data already includes every value you want to analyze.
• Smaller result means tighter clustering: Larger result means more spread.
• Uses the same units as the data: That often makes it easier to interpret than variance.
• Reference behavior: Text and logical values in references are ignored.
• Related option: Use STDEV.S when the data is only a sample.