You may want to get a public key token from a dll assembly especially if you need to have a strong name compiled for your dll file. Those assemblies are usually placed inside GAC or known as Global Assembly Cache. The idea of GAC is to make those assemblies accessible by all of your applications.

There is an easy way to get the public key token. You can easily use the keyword tool built in Visual Studio developer command prompt which is SN. To use it, open the Visual Studio Developer Command on your computer. You then need to run using the following pattern command.

sn -T assembly_path

Please see the following screenshot example on how to do it.