3v4l.org

run code in 300+ PHP versions simultaneously
<?php $l = 'abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-'; $x=0; for ($r=16;$x<$r;$x++) { substr($l,mt_rand(0,strlen($l)-1),1); }
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.7

preferences:
151.35 ms | 404 KiB | 175 Q