$re = '/^(((h..ps?|f.p):\/\/)?(?:([\w\-\.])+(\[?\.\]?)([\w]){2,4}|(?:(?:25[0-5]|2[0-4]\d|[01]?\d\d?)\[?\.\]?){3}(?:25[0-5]|2[0-4]\d|[01]?\d\d?)))*([\w\/+=%&_\.~?\-]*)$/m';
$str = 'www[.]domain[.]com
www.domain.com
hxxp://www[.]domain[.]com
192.168.8.1/folder/file.html
192.168.1[.]1
192.168.1[.]1/folder/file.html
192[.]168[.]1[.]1/folder/file.html
hxxp://www[.]domain[.]com/folder/file.html
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php