3v4l.org

run code in 300+ PHP versions simultaneously
<?php $date = "20.08.2015"; if (preg_match("!^\d+$!", $date)) { $time = gmmktime(0, 0, 0, 1, 1, 1900) + ($date - 2) * 24 * 60 * 60; return gmdate("Y-m-d", $time); }

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60.81 ms | 402 KiB | 5 Q