public static function max_upload_size()
    {
        // find max filesize value
        $max_filesize = parse_bytes(ini_get('upload_max_filesize'));
        $max_postsize = parse_bytes(ini_get('post_max_size'));

        if ($max_postsize && $max_postsize < $max_filesize) {
            $max_filesize = $max_postsize;
        }

        return $max_filesize;
    }