3v4l.org

run code in 300+ PHP versions simultaneously
<?php var_dump( $conv = mb_convert_encoding( $bin = hex2bin("00"), "UTF-8", "UTF7-IMAP" ), mb_check_encoding($bin, "UTF7-IMAP"), bin2hex(mb_convert_encoding($conv, "UTF7-IMAP", "UTF-8")) );
Output for 8.1.0 - 8.1.31, 8.2.0 - 8.2.27, 8.3.0 - 8.3.15, 8.4.1 - 8.4.2
string(1) "?" bool(false) string(2) "3f"
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30
string(1) "" bool(true) string(2) "00"

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