# Excel STDEV Function

The Excel STDEV function returns the standard deviation for data that represents a sample. To calculate the standard deviation for an entire population, use STDEVP or STDEV.P.

**number1**- First number or reference in the sample.**number2**- [optional] Second number or reference.

The STDEV function calculates the standard deviation for a sample set of data. Standard deviation measures how much variance there is in a set of numbers compared to the average (mean) of the numbers. The STDEV function is meant to estimate standard deviation in a sample. If data represents an entire population, use the STDEVP function.

In the example shown, the formula in F7 is:

=STDEV(C5:C11)

*Note: Microsoft classifies STDEV as a "compatibility function", now replaced by the STDEV.S function.*

### Standard Deviation functions in Excel

The table below summarizes the standard deviation functions provided by Excel.

Name | Data set | Text and logicals |
---|---|---|

STDEV | Sample | Ignored |

STDEVP | Population | Ignored |

STDEV.S | Sample | Ignored |

STDEV.P | Population | Ignored |

STDEVA | Sample | Evaluated |

STDEVPA | Population | Evaluated |

Notes:

- STDEV calculates standard deviation using the "n-1" method.
- STDEV assumes data is a sample only. When data represents an entire population, use STDEVP or STDEV.P.
- Numbers are supplied as arguments. They can be supplied as actual numbers, ranges, arrays, or references that contain numbers.
- STDEV ignores text and logical values that occur in references, but evaluates text and logicals hardcoded as function arguments.
- To evaluate logical values and/or text in the calculation, use the STDEVA function.

## Excel Formula Training

Formulas are the key to getting things done in Excel. In this accelerated training, you'll learn how to use formulas to manipulate text, work with dates and times, lookup values with VLOOKUP and INDEX & MATCH, count and sum with criteria, dynamically rank values, and create dynamic ranges. You'll also learn how to troubleshoot, trace errors, and fix problems. Instant access. See details here.