3v4l.org

run code in 300+ PHP versions simultaneously
<?php $date=date('Y-m'); var_dump($date); var_dump(date('Y-m',strtotime("$date -1 month"))); ?>
Output for 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
string(7) "2013-10" string(7) "2013-09"
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5
string(7) "2013-10" string(7) "2013-11"
preferences:
335.13 ms | 402 KiB | 460 Q