Tool to decrypt/encrypt Bacon cipher, a 2-letter substitution alphabet which replace a character with a group of 5 formed with two letters (often A and B).
Bacon Cipher - dCode
Tag(s) : Substitution Cipher
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Bacon Cipher
Baconian Cipher Decoder
Bacon Encoder
Answers to Questions (FAQ)
What is the Bacon cipher? (Definition)
Bacon's encryption uses a substitution alphabet based on 2 letters (sometimes called biliteral or baconian), often A and B, replacing the letters of the alphabet.
This encryption method is often accompanied by over-encryption.
How to encrypt using Bacon cipher?
Baconian encryption uses the substitution table:
| A | AAAAA | B | AAAAB |
|---|---|---|---|
| C | AAABA | D | AAABB |
| E | AABAA | F | AABAB |
| G | AABBA | H | AABBB |
| I=J | ABAAA | K | ABAAB |
| L | ABABA | M | ABABB |
| N | ABBAA | O | ABBAB |
| P | ABBBA | Q | ABBBB |
| R | BAAAA | S | BAAAB |
| T | BAABA | U=V | BAABB |
| W | BABAA | X | BABAB |
| Y | BABBA | Z | BABBB |
Example: DCODE is encrypted AAABB,AAABA,ABBAB,AAABB,AABAA
In this original alphabet (🔤1), the letter V does not exist, it is replaced by U, likewise the letter J does not exist, it is replaced by I.
Another bacon's alphabet (🔤2) is sometimes preferred, more complete, it uses a unique code for each letter:
| A | AAAAA | B | AAAAB |
|---|---|---|---|
| C | AAABA | D | AAABB |
| E | AABAA | F | AABAB |
| G | AABBA | H | AABBB |
| I | ABAAA | J | ABAAB |
| K | ABABA | L | ABABB |
| M | ABBAA | N | ABBAB |
| O | ABBBA | P | ABBBB |
| Q | BAAAA | R | BAAAB |
| S | BAABA | T | BAABB |
| U | BABAA | V | BABAB |
| W | BABBA | X | BABBB |
| Y | BBAAA | Z | BBAAB |
The 2-letter code used can be hidden in an over-encryption. A classic method is to write a random message with upper case (for A) or lower case (for B) or vice versa; in this case see the binarization of uppercase and lowercase. Other methods are possible such as writing certain characters in italics (or in bold), or even mixing 2 fonts.
How to decrypt Bacon cipher?
Baconian decryption is a substitution with Bacon alphabet.
Example: AAABB AAABA ABBAB AAABB AABAA is equivalent to DCODE.
If over-encryption has been applied, convert the message into 2 characters (preferably A and B) first.
How to recognize a Bacon ciphertext?
The ciphered message is a binary code (with 2 distinct characters), and maybe spaces every 5 characters.
Typical cases of over-encryption are alternating upper-lower case letters, bold or italic letters or encoding different character fonts.
All references to Françis Bacon (the painter or the philosopher), Kevin Bacon (actor of Batman), to Novum organum, or to bacon slices (pork, larding, smoked, salted, english breakfast, etc.) are clues.
What are the variants of the Bacon cipher?
The letters A and B can be replaced by others characters, such as 0 and 1, to transform the message into binary format.
Sometimes the letters o and l are used: lolol loolo lolol.
The over-encryptions (of the steganographic type) are sometimes used to mask the binary form (upper case, lower case, variant characters or fonts, etc.).
When was Bacon cipher invented?
Francis Bacon first described the Bacon alphabet around 1605
Source code
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