Tool directory
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Filter:AllClassical CiphersEncoding & DecodingCommunication CodesPuzzle ToolsSecurity & HashingSteganographyNumber Theory
Showing Classical Ciphers (23 tools)
Caesar Cipher
Classical CiphersEncrypt or decrypt messages by shifting letters through the alphabet.
Vigenère Cipher
Classical CiphersPolyalphabetic substitution cipher using a keyword for enhanced encryption.
ROT13 Cipher
Classical CiphersSimple letter substitution cipher that rotates letters by 13 positions.
Atbash Cipher
Classical CiphersReverses the alphabet mapping A to Z, B to Y, and so on for encoding.
Pigpen Cipher
Classical CiphersGrid-based substitution cipher using geometric symbols to represent letters.
Playfair Cipher
Classical CiphersDigraph substitution cipher that encrypts pairs of letters using a 5x5 grid.
Four-Square Cipher
Classical CiphersDual-key digraph cipher using four 5x5 grids for enhanced substitution security.
Hill Cipher
Classical CiphersMatrix-based polygraphic cipher using linear algebra for block encryption.
ADFGVX Cipher
Classical CiphersWWI German field cipher combining fractionation and transposition for military security.
Affine Cipher
Classical CiphersMathematical cipher using linear functions ax + b for letter substitution.
Polybius Square
Classical CiphersAncient Greek coordinate system converting letters to numerical positions for signaling.
Porta Cipher
Classical CiphersRenaissance polyalphabetic cipher using 13 reciprocal substitution pairs.
Gronsfeld Cipher
Classical CiphersNumeric key variant of Vigenère cipher popular in CTF competitions.
Scytale Cipher
Classical CiphersAncient Spartan transposition cipher using cylindrical rod geometry.
Double Transposition
Classical CiphersAdvanced cipher applying columnar transposition twice with dual keywords for enhanced security.
Autokey Cipher
Classical CiphersPolysubstitution cipher that uses the plaintext itself as part of the encryption key.
Beaufort Cipher
Classical CiphersVariant of Vigenère cipher using reciprocal mathematical operation for encryption.
Rail Fence Cipher
Classical CiphersSimple transposition cipher that writes text in a zigzag pattern across multiple rails.
Columnar Transposition
Classical CiphersSophisticated transposition cipher using keyword columns to rearrange text.
Baconian Cipher
Classical CiphersHide binary messages using two different fonts or character representations.
Running Key Cipher
Classical CiphersUses long text passages like book content as the encryption key for enhanced security.
Caesar Brute Force
Classical CiphersTry all 25 Caesar cipher shifts at once with automatic ranking by likelihood.
Vigenère Cracker
Classical CiphersAuto-crack Vigenère ciphers using Kasiski examination and frequency analysis.