3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $yr="2013"; $week="01"; $day="02"; $day=date("D",strtotime($day)); $newdate= date("Y-m-d", strtotime($yr."W".$week));; echo $newdate; ?>
Output for 5.1.0 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
2012-12-31
Output for 5.0.0 - 5.0.5
2012-12-24
Output for 4.3.0 - 4.4.9
1970-01-01