3v4l.org

run code in 300+ PHP versions simultaneously
<?php $string = "\xEF\xBB\xBF\x22\x61\x22\x0A"; var_dump(mb_detect_encoding($string)); $stream = fopen('php://memory', 'w+'); fwrite($stream, $string); rewind($stream); var_dump(fgets($stream, 1000));
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
string(5) "UTF-8" string(7) ""a" "

preferences:
90.83 ms | 1941 KiB | 4 Q