Classical Cryptography & Cipher Decoder
Encrypt or decrypt messages using classical cryptographic ciphers including Caesar Shift, Atbash, ROT13, and Vigenère with custom keys.
Formula
Caesar: C = (P + K) mod 26 | Atbash: C = 25 - P | Vigenère: C_i = (P_i + K_i) mod 26
Source / method note
Based on classical substitution and polyalphabetic cipher mathematical models.
Legal / official rate note
For educational and puzzle-solving purposes.
Frequently Asked Questions
What is the Caesar cipher?
A substitution cipher where each letter in the plaintext is shifted a fixed number of positions down the alphabet.
