$re = '/(?:https?:\/\/)?(?:www\.)?youtu(?:be)?\.(?:com|be)(?:\/watch\/?\?v=|\/embed\/|\/shorts\/|\/)(\w+)/';
$str = 'https://www.youtube.com/watch?v=aQt9BumzZ7M
https://youtu.be/eGJWz3E5HrU
https://www.youtube.com/embed/eGJWz3E5HrU';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php