3v4l.org

run code in 300+ PHP versions simultaneously
<?php $php_ver = phpversion(); $php_ver == "5.6.16" or die(); ECHO phpversion();
Output for 5.5.24 - 5.5.35, 5.6.8 - 5.6.15, 5.6.17 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.13, 7.3.0 - 7.3.1
Output for 5.6.16
5.6.16

preferences:
78.79 ms | 401 KiB | 63 Q