#!/usr/bin/perl

use strict; 
use warnings;

use CGI::Util qw(escape unescape);

use utf8;
print 'äöüßÄÖÜ€ ist: ',escape('äöüßÄÖÜ€');
print "\n";

print '%32%7E ist: ',unescape('%32%7E');
print "\n";
__END__
ergibt:
äöüßÄÖÜ€ ist: %C3%A4%C3%B6%C3%BC%C3%9F%C3%84%C3%96%C3%9C%E2%82%AC
%32%7E ist: 2~