- var_dump: documentation ( source)
- base64_decode: documentation ( source)
<?php
$str = 'UE1CQgNNHEVIDwtXBwRcHA1dTRYCCF9QGgEGDUlVDQ0PFkFFTkx9VU8iCFQWDGpXD11YSgESHVtQRWsoUAcADV0cBAJ6DlJDS0ZWBjEUTBdRCBQcVlFjXFZaEVcJNhRECglvXUwQFgIIKwFXB0QKAkYKAQtUUAAQBwgaF1gR';
var_dump([$str, base64_decode($str), base64_decode(rot13_encode($str))]);