Powershell to list all webs with UI version 3 for sharepoint 2013 upgrade purpose

Add-Pssnapin Microsoft.SharePoint.Powershell

 

$s | Get-SPSite -limit all | ForEach-Object {$site =$_;

$site | Get-SPWeb -limit all | ForEach-Object {

if($_.UIVersion -eq 3)

{

write-host "UI version : " $_.UIVersion  $_.Url

}

}}