Sometimes we need to know the size of lists, but unfortunately we have no cmdlet for. I was curious how can I get it and I found a some useful article on the Internet. That was based for my script which can show you a list attachments storage usage. When you start the script, you should give the site url which contains your list and also give the list title.

 

PowerShell
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param ( 
    [Parameter(Mandatory=$true)] 
    [string]$url = "", 
    [Parameter(Mandatory=$true)] 
    [string]$title = "" 
    ) 
 
If((Get-PSSnapin Microsoft.SharePoint.PowerShell –EA SilentlyContinue) –eq 
$null){Add-PSSnapin Microsoft.SharePoint.PowerShell} 
 
$size = 0 
$web = Get-SPWeb $url  
$web | select -ExpandProperty lists |  
Where {$_.Title -eq "$title"} |  
Select -ExpandProperty Items |  
ForEach-Object {$web.getfolder($_.Attachments.UrlPrefix)} |  
Select -ExpandProperty files |  
ForEach-Object {$size += $_.length} 
"Size of attachments: {0:N2} MB" -f ($size/1MB)