Beaufort Cipher
Polyalphabetic substitution cipher using key letter minus plaintext letter.
The Beaufort cipher, created by Sir Francis Beaufort, is a polyalphabetic substitution cipher similar to the Vigenere cipher. Instead of adding letter values, it calculates each cipher letter by taking the key letter minus the plaintext letter. This tool supports both standard and autokey Beaufort modes. Don't know the keyword? Use Solve automatically to crack it from ciphertext.
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Keyword case doesn't matter (CACHE = cache). The letter case of your text is preserved in the output.
Enter a keyword to derive a custom alphabet, or leave blank for A-Z.
Sets the language statistics the solver scores against. Choose Auto to detect the plaintext language from the ciphertext and switch to it automatically (needs at least ~20 letters). Raise the max keyword length for longer keys, but note that longer keys need more ciphertext to crack reliably.
Auto-solve assumes the standard A-Z alphabet; results won't match if you've set a custom alphabet.
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Tabula Recta
The cipher uses this table for encipherment. Updates when alphabet changes.