SharePoint Online: Find Content Type usage using PowerShell

Requirement: Find where a Content Type is used in SharePoint Online

You may have to find the content type usage in scenarios like,

You are getting "content type is still in use" error when trying to delete a content type.
You are trying to figure out where a particular content type is being used, etc.

PowerShell to Find Content Type Usage in SharePoint Online
Unlike SharePoint On-premises, We don't have SPContentTypeUsage class available in CSOM. So we are left with an option: Scan each and every list to get the content type usage!

#Load SharePoint CSOM Assemblies
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.dll"
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.Runtime.dll"

#Function to get the content type usage 
Function Find-SPOContentTypeUsage([String]$SiteURL)
{
    Try{
        Write-host -f Yellow "Processing Site:" $SiteURL

        #Setup the context
        $Ctx = New-Object Microsoft.SharePoint.Client.ClientContext($SiteURL)
        $Ctx.Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($Cred.Username, $Cred.Password)
    
        #Get All Lists of the Web
        $Ctx.Load($Ctx.Web)
        $Ctx.Load($Ctx.Web.Lists)
        $Ctx.Load($ctx.Web.Webs)
        $Ctx.ExecuteQuery()

        #Get content types of each list from the web
        $ContentTypeUsages=@()
        ForEach($List in $Ctx.Web.Lists)
        {
            $ContentTypes = $List.ContentTypes
            $Ctx.Load($ContentTypes)
            $Ctx.Load($List.RootFolder)
            $Ctx.ExecuteQuery()
            
            #Get List URL
            If($Ctx.Web.ServerRelativeUrl -ne "/")
            {
                $ListURL=  $("{0}{1}" -f $Ctx.Web.Url.Replace($Ctx.Web.ServerRelativeUrl,''), $List.RootFolder.ServerRelativeUrl)
            }
            else
            {
                $ListURL=  $("{0}{1}" -f $Ctx.Web.Url, $List.RootFolder.ServerRelativeUrl)
            }
  
            #Get each content type data
            ForEach($CType in $ContentTypes)
            {
                $ContentTypeUsage = New-Object PSObject
                $ContentTypeUsage | Add-Member NoteProperty SiteURL($SiteURL)
                $ContentTypeUsage | Add-Member NoteProperty ListName($List.Title)
                $ContentTypeUsage | Add-Member NoteProperty ListURL($ListURL)
                $ContentTypeUsage | Add-Member NoteProperty ContentTypeName($CType.Name)
                $ContentTypeUsages += $ContentTypeUsage
            }
        }
        #Export the result to CSV file
        $ContentTypeUsages | Export-CSV $ReportOutput -NoTypeInformation -Append

         #Iterate through each subsite of the current web and call the function recursively
        foreach ($Subweb in $Ctx.web.Webs)
        {
            #Call the function recursively to process all subsites underneaththe current web
            Find-SPOContentTypeUsage($Subweb.url)
        }
    }
    Catch {
    write-host -f Red "Error Generating Content Type Usage Report!" $_.Exception.Message
    }
}

#Config Parameters
$SiteURL="https://crescent.sharepoint.com"
$ReportOutput ="C:\Temp\ContentTypeUsage.csv"

#Get Credentials to connect
$Cred= Get-Credential

#Delete the Output Report, if exists
if (Test-Path $ReportOutput) { Remove-Item $ReportOutput }

#Call the function to get the content type usage
Find-SPOContentTypeUsage $SiteURL

Here is the sample output of the script.

This PowerShell script gets all content types of all lists and libraries in a SharePoint Online site collection. What if you want to find where a specific content type is used?

SharePoint Online: Find Where a Specific Content Type is used using PowerShell
Here is how to get content type usage with PowerShell in SharePoint Online.

#Load SharePoint CSOM Assemblies
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.dll"
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.Runtime.dll"

#Function to get a particular content type usage
Function Get-SPOContentTypeUsage([String]$SiteURL, [String]$ContentTypeName)
{
    Try{
        Write-host -f Yellow "Processing Site:" $SiteURL

        #Setup the context
        $Ctx = New-Object Microsoft.SharePoint.Client.ClientContext($SiteURL)
        $Ctx.Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($Cred.Username, $Cred.Password)
    
        #Get All Lists of the Web
        $Ctx.Load($Ctx.Web)
        $Ctx.Load($Ctx.Web.Lists)
        $Ctx.Load($ctx.Web.Webs)
        $Ctx.ExecuteQuery()

        #Get content types of each list from the web
        $ContentTypeUsages=@()
        ForEach($List in $Ctx.Web.Lists)
        {
            $ContentTypes = $List.ContentTypes
            $Ctx.Load($ContentTypes)
            $Ctx.Load($List.RootFolder)
            $Ctx.ExecuteQuery()
            
            #Get List URL
            If($Ctx.Web.ServerRelativeUrl -ne "/")
            {
                $ListURL=  $("{0}{1}" -f $Ctx.Web.Url.Replace($Ctx.Web.ServerRelativeUrl,''), $List.RootFolder.ServerRelativeUrl)
            }
            else
            {
                $ListURL=  $("{0}{1}" -f $Ctx.Web.Url, $List.RootFolder.ServerRelativeUrl)
            }
  
            #Get each content type data
            ForEach($CType in $ContentTypes)
            {
                If($CType.Name -eq $ContentTypeName)
                {
                    $ContentTypeUsage = New-Object PSObject
                    $ContentTypeUsage | Add-Member NoteProperty SiteURL($SiteURL)
                    $ContentTypeUsage | Add-Member NoteProperty ListName($List.Title)
                    $ContentTypeUsage | Add-Member NoteProperty ListURL($ListURL)
                    $ContentTypeUsage | Add-Member NoteProperty ContentTypeName($CType.Name)
                    $ContentTypeUsages += $ContentTypeUsage
                    Write-host -f Green "Found the Content Type at:" $ListURL
                }
            }
        }
        #Export the result to CSV file
        $ContentTypeUsages | Export-CSV $ReportOutput -NoTypeInformation -Append

         #Iterate through each subsite of the current web and call the function recursively
        foreach ($Subweb in $Ctx.web.Webs)
        {
            #Call the function recursively to process all subsites underneaththe current web
            Get-SPOContentTypeUsage $Subweb.url $ContentTypeName
        }
    }
    Catch {
    write-host -f Red "Error Generating Content Type Usage Report!" $_.Exception.Message
    }
}

#Config Parameters
$SiteURL="https://crescent.sharepoint.com"
$ReportOutput ="C:\Temp\ContentTypeUsage.csv"
$ContentTypeName="Business Contacts"

#Get Credentials to connect
$Cred= Get-Credential

#Delete the Output Report, if exists
if (Test-Path $ReportOutput) { Remove-Item $ReportOutput }

#Call the function to get the content type usage
Get-SPOContentTypeUsage $SiteURL $ContentTypeName

This gets you all locations of the specific content type usage.

Please note, you can not delete a content type as long as the content type is in use on any of the SharePoint site. Also, In order to remove a content type from SharePoint site, any item that uses the particular content type must be either change its content type or completely removed even from recycle bins (1st stage & 2nd stage recycle bins).

Here is my another post to find where a content type is used in SharePoint On-premises: Find Content Type Usage in SharePoint using PowerShell

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