3v4l.org

run code in 500+ PHP versions simultaneously
<?php $str = "\ud83d\ude01"; $str = json_decode('"' . $str . '"'); $bytes = str_split($str); for ($i = 0; $i < count($bytes); $i++) { $bytes[$i] = "\x" . dechex(ord($bytes[$i])); } $str = implode('',$bytes); echo $str;

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96.65 ms | 2685 KiB | 5 Q