Interactive Identification

Cipher Detective

Paste unknown ciphertext below. The engine will run statistical tests to identify the most likely cryptographic family based on Index of Coincidence, chi-square, and structure.

Awaiting input. Mathematical analysis will appear instantly as you type or paste text.

Limitations

The Detective relies on standard English text frequencies. It will be less accurate for:

  • Very short messages (under 20 characters).
  • Plaintext in languages other than English.
  • Texts heavily skewed with names, acronyms, or non-standard vocabulary.
  • Ciphers utilizing nulls or non-standard alphabets.

Cryptanalytic Profile

Length -
Characters -
IoC -
Base Chi-Square -
Best Shift -
Probable Period -
Learn these metrics →