<?php
$encoding = 'ASCII';
$known_encodings = mb_list_encodings();
if (in_array($encoding, $known_encodings)) {
$aliases = mb_encoding_aliases($encoding);
print_r($aliases);
} else {
echo "Unknown ($encoding) encoding.\n";
}
?>
Array
(
[0] => ANSI_X3.4-1968
[1] => iso-ir-6
[2] => ANSI_X3.4-1986
[3] => ISO_646.irv:1991
[4] => US-ASCII
[5] => ISO646-US
[6] => us
[7] => IBM367
[8] => cp367
[9] => csASCII
)