Chaocipher

How Chaocipher works

Chaocipher handles letters through two alphabets that permute after every character, so the substitution relationship continually changes throughout the message. The plaintext character is located in the right alphabet and read from the left; both alphabets then rotate and perform their specified zenith insertions before the next letter. The Chaocipher exposes its message, left alphabet, right alphabet, operation controls so this particular convention stays inspectable instead of hiding behind an unexplained preset.

Using Moshe Rubin's standard starting alphabets, WELLDONEISBETTERTHANWELLSAID produces OAHQHCNYNXTSZJRRHJBYHQKSOUJY exactly. Cipher historians can reproduce the canonical vector or replace either alphabet to inspect the machine-like evolving substitution by hand. The Chaocipher presents a deterministic plain-text result that can be copied and compared with the worked value before it enters another workflow.

Limits and private processing

Each starting alphabet must contain A through Z exactly once, nonletters are removed, and the historical design is unsuitable for real confidential communication. The Chaocipher performs its complete operation locally in your browser; neither the source text nor its settings are uploaded, stored remotely, or sent through an external request.