Beaufort Cipher: Encryption and Translation Online Beaufort cipher is a substitution cipher and a variant of Vigenère cipher. Encryption and decryption using Beaufort cipher is achieved though the same algorithm. While Vigenère cipher adds the key to the plaintext, beaufort cipher subtracts the plaintext to the key. It was invented by Sir Francis Beaufort in 1857. It has been applied in rotor based cipher machines like the Hagelin M-209. Beaufort code is based on Beaufort square which is very similar to Vigenère square but in reverse order. This cipher uses a table called “Recta”, which was commonly used with the Trithemius cipher. Use the above beaufort cipher decoder and encoder to encrypt/decrypt simple messages. If this tool was helpful, tweet it or share it.