3v4l.org

run code in 300+ PHP versions simultaneously
<?php $year = 2015; $year -= date("Y"); echo strtotime("first day of january -1 year");
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.29 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4

preferences:
169.78 ms | 404 KiB | 218 Q