3v4l.org

run code in 300+ PHP versions simultaneously
<?php $date = new DateTime('2016-05-31'); echo $date->format('Y-m-d') . PHP_EOL; echo $date->modify('-1 month')->format('Y-m-d') . PHP_EOL; echo PHP_EOL; $date = new DateTime('2016-05-31'); echo $date->format('Y-m-d') . PHP_EOL; echo $date->modify('+1 month')->format('Y-m-d') . PHP_EOL; echo PHP_EOL; $date = new DateTime('2016-07-01'); echo $date->format('Y-m-d') . PHP_EOL; echo $date->modify('-1 month')->format('Y-m-d') . PHP_EOL;
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
2016-05-31 2016-05-01 2016-05-31 2016-07-01 2016-07-01 2016-06-01

preferences:
137.79 ms | 403 KiB | 174 Q