# How do I find what Perl modules are installed on my system?

Assuming you have perldoc installed, simply typing `perldoc perllocal` will give you a nicely-formatted detailed list of all the installed Perl modules.

For a simpler list that simply prints out the module names and their version numbers, there is another alternative. You must have the [ExtUtils::Installed](http://search.cpan.org/~jhi/perl-5.8.0/lib/ExtUtils/Installed.pm) module installed in order to use it. Enter this code into a file and have Perl run it.  
`#!/usr/local/bin/perl`  
`use ExtUtils::Installed;`  
`my $instmod = ExtUtils::Installed->new();`  
`foreach my $module ($instmod->modules()) {`  
`my $version = $instmod->version($module) || "???";`  
@ print “$module — $version\\n”;@  
`}`

See [this page from the <span class="caps">CPAN</span> <span class="caps">FAQ</span>](http://www.cpan.org/misc/cpan-faq.html#How_installed_modules) for more details.

The *Perl Cookbook* contains an example program that will give an extremely thorough listing of each module (and their sub-modules) from every Perl directory you have, called `pmdesc`. The program can be downloaded for free at: [http://examples.oreilly.com/cookbook/](http://examples.oreilly.com/cookbook/). It’s found in Section 12.19. This book is in UCLA’s licensed copy of [O’Reilly’s Safari Online](http://proquest.safaribooksonline.com/) so you can read more about it there.