3v4l.org

run code in 300+ PHP versions simultaneously
<?php $str = 'asdfnsdfasdjkl <b>asdfsdfds</b> asdfkjsadfasd'; printf (preg_replace('/<b>(.*?)<\/b>/', '$1$1', $str));

preferences:
38.12 ms | 402 KiB | 5 Q