Extracting Nupkg files using command line

NuPKG files are just zip files, so anything that can process a zip file should be able to process a nupkg file, i.e, 7zip.

You can also use the NuGet command line, by specifying a local host as part of an install. For example if your package is stored in the current directory

nuget install MyPackage -Source %cd% -OutputDirectory packages

will unpack it into the target directory.