A ruby-based encoding guesser, outputs a github-flavored-markdown table of all the possible encoding interpretations for one or more byte sequences

example.md

	\xA7	\xE9
ASCII-8BIT	(Encoding::UndefinedConversionError) "\xA7" from ASCII-8BIT to UTF-8	(Encoding::UndefinedConversionError) "\xE9" from ASCII-8BIT to UTF-8
Big5	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on Big5	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on Big5
Big5-HKSCS	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on Big5-HKSCS	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on Big5-HKSCS
Big5-UAO	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on Big5-UAO	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on Big5-UAO
CESU-8	(Encoding::InvalidByteSequenceError) "\xA7" on CESU-8	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on CESU-8
CP51932	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on CP51932	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on CP51932
CP850	º	Ú
CP852	ž	Ú
CP855	–î	–∂
CP949	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on CP949	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on CP949
CP950	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on CP950	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on CP950
CP951	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on CP951	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on CP951
EUC-JIS-2004	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on EUC-JIS-2004	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on EUC-JIS-2004
EUC-JP	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on EUC-JP	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on EUC-JP
EUC-KR	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on EUC-KR	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on EUC-KR
EUC-TW	(Encoding::ConverterNotFoundError) code converter not found (EUC-TW to UTF-8)	(Encoding::ConverterNotFoundError) code converter not found (EUC-TW to UTF-8)
Emacs-Mule	(Encoding::ConverterNotFoundError) code converter not found (Emacs-Mule to UTF-8)	(Encoding::ConverterNotFoundError) code converter not found (Emacs-Mule to UTF-8)
GB12345	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on GB12345	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on GB12345
GB18030	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on GB18030	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on GB18030
GB1988	(Encoding::ConverterNotFoundError) code converter not found (GB1988 to UTF-8)	(Encoding::ConverterNotFoundError) code converter not found (GB1988 to UTF-8)
GB2312	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on GB2312	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on GB2312
GBK	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on GBK	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on GBK
IBM437	º	Θ
IBM720	ÿØ	ŸÑ
IBM737	π	ώ
IBM775	¦	ķ
IBM852	ž	Ú
IBM855	–î	–∂
IBM857	ğ	Ú
IBM860	º	Θ
IBM861	Ú	Θ
IBM862	º	Θ
IBM863	¯	Θ
IBM864	(Encoding::ConverterNotFoundError) code converter not found (IBM864 to UTF-8)	(Encoding::ConverterNotFoundError) code converter not found (IBM864 to UTF-8)
IBM865	º	Θ
IBM866	–∑	—â
IBM869	Δ	ο
ISO-8859-1	§	é
ISO-8859-10	§	é
ISO-8859-11	ง	้
ISO-8859-13	§	é
ISO-8859-14	§	é
ISO-8859-15	§	é
ISO-8859-16	§	é
ISO-8859-2	§	é
ISO-8859-3	§	é
ISO-8859-4	§	é
ISO-8859-5	–á	—â
ISO-8859-6	(Encoding::UndefinedConversionError) "\xA7" from ISO-8859-6 to UTF-8	Ÿâ
ISO-8859-7	§	ι
ISO-8859-8	§	י
ISO-8859-9	§	é
KOI8-R	‚ïñ	–ò
KOI8-U	—ó	–ò
MacJapanese	(Encoding::ConverterNotFoundError) code converter not found (MacJapanese to UTF-8)	(Encoding::ConverterNotFoundError) code converter not found (MacJapanese to UTF-8)
SJIS-DoCoMo	ÔΩß	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on SJIS-DOCOMO
SJIS-KDDI	ÔΩß	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on SJIS-KDDI
SJIS-SoftBank	ÔΩß	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on SJIS-SoftBank
Shift_JIS	ÔΩß	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on Shift_JIS
TIS-620	ง	้
US-ASCII	(Encoding::InvalidByteSequenceError) "\xA7" on US-ASCII	(Encoding::InvalidByteSequenceError) "\xE9" on US-ASCII
UTF-16BE	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on UTF-16BE	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on UTF-16BE
UTF-16LE	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on UTF-16LE	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on UTF-16LE
UTF-32BE	(Encoding::InvalidByteSequenceError) "\xA7" on UTF-32BE	(Encoding::InvalidByteSequenceError) "\xE9" on UTF-32BE
UTF-32LE	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on UTF-32LE	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on UTF-32LE
UTF-8	ß	È
UTF8-DoCoMo	(Encoding::InvalidByteSequenceError) "\xA7" on UTF8-DoCoMo	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on UTF8-DoCoMo
UTF8-KDDI	(Encoding::InvalidByteSequenceError) "\xA7" on UTF8-KDDI	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on UTF8-KDDI
UTF8-MAC	(Encoding::InvalidByteSequenceError) "\xA7" on UTF8-MAC	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on UTF8-MAC
UTF8-SoftBank	(Encoding::InvalidByteSequenceError) "\xA7" on UTF8-SoftBank	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on UTF8-SoftBank
Windows-1250	§	é
Windows-1251	§	й
Windows-1252	§	é
Windows-1253	§	ι
Windows-1254	§	é
Windows-1255	§	י
Windows-1256	§	é
Windows-1257	§	é
Windows-1258	(Encoding::ConverterNotFoundError) code converter not found (Windows-1258 to UTF-8)	(Encoding::ConverterNotFoundError) code converter not found (Windows-1258 to UTF-8)
Windows-31J	ÔΩß	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on Windows-31J
Windows-874	ง	้
eucJP-ms	(Encoding::InvalidByteSequenceError) incomplete "\xA7" on eucJP-ms	(Encoding::InvalidByteSequenceError) incomplete "\xE9" on eucJP-ms
macCentEuro	(Encoding::ConverterNotFoundError) code converter not found (macCentEuro to UTF-8)	(Encoding::ConverterNotFoundError) code converter not found (macCentEuro to UTF-8)
macCroatian	ß	È
macCyrillic	–Ü	–π
macGreek	ß	ι
macIceland	ß	È
macRoman	ß	È
macRomania	ß	È
macThai	(Encoding::ConverterNotFoundError) code converter not found (macThai to UTF-8)	(Encoding::ConverterNotFoundError) code converter not found (macThai to UTF-8)
macTurkish	ß	È
macUkraine	–Ü	–π
stateless-ISO-2022-JP	(Encoding::InvalidByteSequenceError) "\xA7" on stateless-ISO-2022-JP	(Encoding::InvalidByteSequenceError) "\xE9" on stateless-ISO-2022-JP
stateless-ISO-2022-JP-KDDI	(Encoding::InvalidByteSequenceError) "\xA7" on stateless-ISO-2022-JP-KDDI	(Encoding::InvalidByteSequenceError) "\xE9" on stateless-ISO-2022-JP-KDDI

transcode.rb

# provide our input strings, using ruby's backslash + lower-x + upper-hex + upper-hex
# to represent each non-printable or non-lower-ascii byte:
inputs = [
  "\xA7",
  "\xE9",
].map do |input|
  # we "force" the encoding to be UTF-8,
  # effectively marking it _as_ UTF-8 without
  # changing the bytes it contains
  input.force_encoding(Encoding::UTF_8).freeze
end.freeze

out = $stdout

# we then build a github-flavored-markdown table using _all_ of the non-dummy encodings
# available to ruby, with the results of the transcode operation as the column value
# (whether it be an exception or a valid result)

out.write "|     | `#{inputs.map(&:dump).map{|d| d[1...-1]}.join('` | `')}` |\n"
out.write "| --- | #{inputs.map {|_| '---' }.join(' | ')} |\n"
Encoding.list.reject(&:dummy?).sort_by(&:name).each do |encoding|
  out.write "| #{encoding.name} | "
  inputs.each do |input|
    out.write "`#{input.encode(Encoding::UTF_8, encoding) rescue %Q[(#{$!.class}) #{$!.message}]}` |"
  end
  out.write "\n"
end