3v4l.org

run code in 300+ PHP versions simultaneously
<?php $month = '11'; $month = Date("m", strtotime("2017-" . $month . "-01" . " +1 month")); echo $month;
Output for 7.0.0 - 7.0.25, 7.1.0 - 7.1.20, 7.2.5 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.30, 8.2.0 - 8.2.26, 8.3.0 - 8.3.14, 8.4.1
12

preferences:
79.78 ms | 407 KiB | 5 Q