Myszkowski Transposition Cipher

About this calculator

The Myszkowski transposition cipher is a variant of the columnar transposition cipher where the encryption keyword is allowed to contain repeated letters. In a standard columnar transposition, each keyword letter gets its own unique rank to determine column reading order; in Myszkowski's version, repeated letters share the same rank number, and all columns sharing that number are read together left-to-right (row by row) before moving to the next rank — a subtle twist that changes the resulting ciphertext pattern compared to the classic method.

Named after Émile Myszkowski, who published the technique in 1902, this cipher is studied primarily in classical cryptography courses and puzzle/code-breaking communities as an example of how small structural changes to a transposition scheme affect its security and the statistical patterns left in ciphertext. It's a manual, pre-computer cipher — not used for real security today — but remains a staple teaching example for how transposition (as opposed to substitution) ciphers work.