3v4l.org

run code in 300+ PHP versions simultaneously
<?php $c = json_encode(["foo"=>["password"=>"foo\\\"bar"]]); echo $c; echo preg_replace('{("password"\s*:\s*)"(?:\\\\\\\\)*"}', '$1"****"', $c);

preferences:
51.49 ms | 402 KiB | 5 Q