encoding.hex
Bytes to lowercase hexadecimal text and back (RFC 4648 base16), strictly, identically in every language.
A group of 2:
hex_encode, hex_decodeTagged encode
3 capabilities
encoding.base64
Bytes to base64 and base64url text and back (RFC 4648), with strict decoding, identically in every language.
A group of 4:
base64_encode, base64_decode, base64_url_encode, base64_url_decode
encoding.utf8
Text to UTF-8 bytes and strictly back (RFC 3629), so hashing and signing see the same bytes in every language.
A group of 2:
utf8_encode, utf8_decode