Answer · Kryptos

K5 uses a different key or method and adds little to K4.

Still possibleAnswers 1 questionDeduced0

Where it stands

Still possibleIts tests haven't settled it: one piece of evidence for, none against. It needs two reviews to be accepted.

What it predicts

K5's statistics differ from K4's.

What would rule it out

K5 shares ciphertext with K4 at matching positions.

Evidence 1 for · none against

The auction listed K5 as a 1988 'alternate K4 plain text and coding chart', which could mean a separate chart.

Speculative

FOR

The questions it answers

What is K5 and will it be released?

Part of Is K4 solved, known but withheld, or open?

Open3 answers, none ahead

Cite it

Mysteries Department. (2026). K5 uses a different key or method and adds little to K4. [Answer ANS0D7HTG3R0HFP]. https://mysteriesdept.com/r/ANS0D7HTG3R0HFP

@misc{mysteriesdept_ans0d7htg3r0hfp,
  title     = {K5 uses a different key or method and adds little to K4.},
  author    = {{Mysteries Department}},
  year      = {2026},
  note      = {Answer, catalog key ANS0D7HTG3R0HFP},
  url       = {https://mysteriesdept.com/r/ANS0D7HTG3R0HFP}
}