## Purpose

## Return value

## Arguments

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

## Syntax

## Usage notes

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.