3v4l.org

run code in 300+ PHP versions simultaneously
<?php date_default_timezone_set("UTC"); echo (new DateTime("2016-06-19"))->modify("Monday this week")->format("c"), PHP_EOL; echo (new DateTime("2016-06-19"))->format("W"), PHP_EOL, (new DateTime("2016-06-20"))->format("W"), PHP_EOL;
Output for 5.6.23 - 5.6.40, 7.0.8 - 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
2016-06-13T00:00:00+00:00 24 25
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.22, 7.0.0 - 7.0.7
2016-06-20T00:00:00+00:00 24 25
preferences:
161.45 ms | 407 KiB | 5 Q