I can think of some heuristics to do this involving regular expressions, however, I am sure there are exceptions to my rules and cases which I have never seen rendering my technique invalid. I was thinking of something like the following: 
my $tld;
my $url = 'http://www.someurl.com/index.html';
if($url =~ /(http:\/\/)?(.+?)\//)
{
my $host = $2;
my @host_parts = split(/\./, $host);
my $len = @host_parts;
if(length($host_parts[-1]) <= 2 && $len > 2)
{
$tld = join('.',@host_parts[-2..-1]);
}
else
{
$tld = $host_parts[-1];
}
}

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Can any monks think of how to improve this? Is there any module for doing the following which i didnt find?

In reply to Finding the Top Level Domain from a URL by downer

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