3v4l.org

run code in 300+ PHP versions simultaneously
<?php $str = 'ั‚ะตัั‚12qq'; $str_win = iconv('utf-8', 'cp1251//IGNORE', $str); echo mb_detect_encoding($str_win); echo iconv('utf-8', 'cp1251//IGNORE', $str);

preferences:
61.92 ms | 405 KiB | 6 Q