The subject of character mapping and encoding is formidable, and many confuse the various schemes and standards available. As a reference, the list below gives the main encoding options and their associated output sizes.
ASCII -> 7 bits
“Extended ASCII” -> 8 bits
UTF-7 -> 7 bits
IBM (OEM) Code Maps -> 8 bits
ANSI (Microsoft) Code Maps -> 8 bits
ISO 8859 -> 8 bits
UTF-8 -> 1-4 bytes
UTF-16 -> 2-4 bytes
UTF-32 -> 4 bytes
UCS-2 -> 2 bytes (obsolete)
UCS-4 -> 4 bytes