PowerShell: How to Count Items by Group

Often you may want to count the number of items in each group in an object in PowerShell.

You can use the following syntax to do so:

$my_data | Group-Object team | Select-Object Name, Count

This particular example returns the count of items in each group of the object named $my_data, which has been grouped by the team property.

Here is what the various commands do:

Group-Object team: Group the rows in the $my_data object based on the team property.
Select-Object: Specifies that only the group name (in this case the team value) and count should be returned.

The following example shows how to use this syntax in practice.

Example: How to Count Items by Group in PowerShell

Suppose that we have a file named nba_data.csv that contains information about various basketball players.

We can use the following syntax to import this CSV file into an object named $my_data:

$my_data = Import-Csv nba_data.csv

The following screenshot shows how to use this syntax in practice:

Suppose that we would like to count the number of rows for each unique value in the team column.

We can use the following syntax to do so:

$my_data | Group-Object team | Select-Object Name, Count

The following screenshot shows how to use this syntax in practice:

PowerShell count by group

Notice that this returns the name of each unique value from the team column along with the count of each team.

Note: You can find the complete documentation for the Group-Object cmdlet in PowerShell here.