PowerShell: Get Folder Sizes on Disk in Windows

The most of Windows users get used that the easiest way to check the size of a folder is to open the folder properties in Windows Explorer. More experienced users prefer to use tools like TreeSize or WinDirStat. However, if you want to get a detailed statistics on the size of folders in the specific directory or exclude certain file types, you’d better use the PowerShell scripts. In this article we’ll show you how to quickly get the size of the specific folder on the disk (or all subfolders) using PowerShell.

You can use the Get-ChildItem (gci alias) and Measure-Object (measure alias) cmdlets to get the sizes of files and directories in PowerShell.

The first cmdlet allows you to get the list of files in the specified directory by the certain criteria, and the second one performs an arithmetic operation.

For example, to get the size of c:\ps folder, run the following command:

Get-ChildItem c:\iso | Measure-Object -Property Length -sum

As you can see, the total size of files in this directory is shown in the Sum field and is about 2.1 GB (the size is given in bytes).

To convert the size into more convenient MB or GB, use this command:

(gci c:\iso | measure Length -s).sum / 1Gb

Or:

(gci c:\iso | measure Length -s).sum / 1Mb

To round the result to two decimals, run the following command:

"{0:N2} GB" -f ((gci c:\iso | measure Length -s).sum / 1Gb)

To calculate the total size of all files of a certain type in a directory, use this command (for example you want to get the total size of all ISO files in a folder):

(gci c:\iso *.iso | measure Length -s).sum / 1Mb

The commands shown above allow you to get only the total size of files in the specified directory. If there are subfolders in the directory, the size of files in the subfolders won’t be calculated. To get the total size of files in the directory taking subfolders into account, use the –Recurse parameter. Let’s get the total size of files in the C:\Windows directory:

"{0:N2} GB" -f ((gci –force c:\Windows –Recurse -ErrorAction SilentlyContinue| measure Length -s).sum / 1Gb)

To take into account the size of hidden and system files, I have used the –force argument as well.

So the size of C:\Windows on my local drive is about 16 GB.

You can get the size of all first-level subfolders in the specified directory. For example, you want to get the size of all user profiles in the folder C:\Users.

gci -force 'C:\Users'-ErrorAction SilentlyContinue | ? { $_ -is [io.directoryinfo] } | % {
$len = 0
gci -recurse -force $_.fullname -ErrorAction SilentlyContinue | % { $len += $_.length }
$_.fullname, '{0:N2} GB' -f ($len / 1Gb)
}

% is an alias for the foreach-object cycle.

Let’s go on. Suppose, your task is to find the size of each directory in the root of the system hard drive and present the information in the convenient table form for analysis and able to be sorted by the folder size. To do it, let’s use the Out-GridView cmdlet.

To get the information about the size of directories on the drive C:\, run the following PowerShell script:

$targetfolder='C:\'
$dataColl = @()
gci -force $targetfolder -ErrorAction SilentlyContinue | ? { $_ -is [io.directoryinfo] } | % {
$len = 0
gci -recurse -force $_.fullname -ErrorAction SilentlyContinue | % { $len += $_.length }
$foldername = $_.fullname
$foldersize= '{0:N2}' -f ($len / 1Gb)
$dataObject = New-Object PSObject
Add-Member -inputObject $dataObject -memberType NoteProperty -name “foldername” -value $foldername
Add-Member -inputObject $dataObject -memberType NoteProperty -name “foldersizeGb” -value $foldersize
$dataColl += $dataObject
}
$dataColl | Out-GridView -Title “Size of subdirectories”

As you can see, the graphic view of the table should appear where all folders in the root of the system drive C:\ and their size are shown. By clicking the column header, you can sort the folders by size.