Online PHP editor | refs for 2P9kj

<?php function getPrevMonthDatetime($datetime) { return date('Y-m-d H:i:s', strtotime('today last month 00:00:00', strtotime($datetime))); } for ($datetime = '2016-01-01 00:00:00'; strtotime($datetime) < strtotime('2017-01-01 00:00:00'); $datetime = date('Y-m-d H:i:s', strtotime($datetime)+60*60*24)) { echo $datetime.' -> '.getPrevMonthDatetime($datetime)."\n"; }