3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php preg_match('/robot|spider|crawler|curl|^$/i', $_SERVER['HTTP_USER_AGENT']);
based on pWBIB
Output for 5.3.0 - 7.1.0
Notice: Undefined index: HTTP_USER_AGENT in /in/XTcC2 on line 3
Output for 4.3.0 - 5.2.17
Notice: Undefined index: HTTP_USER_AGENT in /in/XTcC2 on line 3