3v4l.org

run code in 300+ PHP versions simultaneously
<?php header_register_callback(function () { echo 'header'; register_shutdown_function(function () { echo 'shutdown'; }); });
Output for 5.5.0 - 5.5.35, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
header
preferences:
111.04 ms | 1616 KiB | 4 Q