3v4l.org

run code in 300+ PHP versions simultaneously
<?php var_dump( $conv = mb_convert_encoding( $bin = hex2bin("0001f1e8"), "UTF-8-Mobile#KDDI-A", "UCS-4BE" ), mb_check_encoding($bin, "UTF-8-Mobile#KDDI-A"), bin2hex(mb_convert_encoding($conv, "UTF-8-Mobile#KDDI-A", "UTF-8")) );
Output for 8.1.0 - 8.1.30, 8.2.0 - 8.2.24, 8.3.0 - 8.3.12
string(1) "?" bool(false) string(2) "3f"
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30
string(0) "" bool(false) string(0) ""
preferences:
58.94 ms | 407 KiB | 5 Q