3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = array(); $t = microtime(true); for ($i = 0; $i < 400000; ++$i) $a[] = rand(); sleep (1000); echo (microtime(true) - $t) / 1000;
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.7

Process exited with code 137.

preferences:
66.02 ms | 402 KiB | 34 Q