3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php ob_start(); header("X-WTFIDONTEVEN: true"); if (headers_sent()) { echo "sent"; } else { echo "not sent"; } ob_end_clean();
Output for 4.3.0 - 5.6.28, hhvm-3.10.0 - 3.13.2, 7.0.0 - 7.1.0