Find difference between two dates in days. PHP 5.2.x.

date_diff.php

<?php
    /**
     * Find difference between two dates in days. PHP 5.2.x.
     */

    $d1 = date('Y-m-d', strtotime('2013-06-13 12:27:43'));
    $d2 = date("Y-m-d");
    echo diff($d1, $d2);

    function diff($date1, $date2) {
        $diff = abs(strtotime($date2) - strtotime($date1));

        $years = floor($diff / (365*60*60*24));
        $months = floor(($diff - $years * 365*60*60*24) / (30*60*60*24));
        $days = floor(($diff - $years * 365*60*60*24 - $months*30*60*60*24) / (60*60*24));

        return $days;
    }
?>