3v4l.org

run code in 500+ PHP versions simultaneously
<?php $atcode = '11F5796B61690196'; var_export( strtr( str_repeat(substr($atcode, -2), 2), '012345789ABCDEF', '2301675AB89EFCD' ) );
Output for 8.1.0 - 8.1.34, 8.2.0 - 8.2.31, 8.3.0 - 8.3.31, 8.4.1 - 8.4.23, 8.5.0 - 8.5.8
'B6B6'
preferences:
68.81 ms | 1018 KiB | 4 Q