BaseEncode

BaseEncode[ba] encodes the byte array ba as a Base64 string.

BaseEncode[ba, "encoding"] encodes using the specified encoding.

Examples

Encode to Base64:

BaseEncode[ByteArray[{72, 101, 108, 108, 111}]]
(* "SGVsbG8=" *)

Please visit the official Wolfram Language Reference for more details.