How to find out which w3wp.exe PID corresponds to which application pool?

Should we have more than one website hosted on IIS, it may be difficult to identify which web application is the one listed on the task manager especially when the application pools are all on Network Service.

Task Manager showing multiple w3wp.exe processes

Each w3wp.exe process has a PID (process identifier), but to tell which PID belongs to which application pool, it is not straightforward.

One method to find out the application pool is to run the appcmd command on command prompt from C:\Windows\system32\inetsrv directory.

appcmd list wp

appcmd command to show application pool of a PID

Simply match the PID against the application pool name. I hope it helps.