- date: documentation ( source)
- strtotime: documentation ( source)
<?php
$result = strtotime('10/16/2003');
// $newDate = date("Y-m-d", strtotime($result));
$cstBirthday = date('Y-m-d',$result);
echo $cstBirthday->format('Y-m-d');
//echo $startTime->format('Y-m-d H:i:s');