3v4l.org

run code in 300+ PHP versions simultaneously
<?php $d = new DateTime("2017-04-19"); $d->modify('last day of previous month'); echo $d->format('Y-m-d');
Output for 5.6.38 - 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 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
2017-03-31

preferences:
104.78 ms | 1760 KiB | 4 Q