3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $yr="2014"; $dif=2012-$yr; $week="01"; $day="Monday"; $day=date("D",strtotime($day)); echo date("Y-m-d", strtotime($yr."W".$week."D ".$day)+86000*$dif);; ?>
Output for 5.2.0 - 7.1.0
2014-01-01
Output for 5.1.0 - 5.1.6
2013-12-27
Output for 5.0.0 - 5.0.5
2013-12-20
Output for 4.3.0 - 4.4.9
1969-12-30