3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php echo preg_replace('/([\?&]clientId=)[0-9a-f]{0,20}/', '${1}23', '/page?clientId=&amp;url=ht');
Output for 4.3.0 - 7.1.0
/page?clientId=23&amp;url=ht