Bacon Cipher
Encode and decode text using the Baconian cipher — each letter is represented as a 5-character sequence of As and Bs (binary-style encoding invented by Francis Bacon).
What Does This Tool Do?
The Bacon cipher (invented by Francis Bacon in 1605) encodes each letter as a 5-character sequence of As and Bs — essentially a 5-bit binary encoding. It was originally used for steganography, hiding messages in text with two different typefaces.
Key Features
A/B Encoding
Each letter becomes 5-char A/B sequence.
Both Directions
Encode text or decode A/B groups.
Historical
Invented by Francis Bacon circa 1605.
Copy Result
One-click copy.
How to Use
- Type or paste your text.
- Click Encode to convert to A/B groups.
- To decode, paste A/B groups separated by spaces and click Decrypt.
Frequently Asked Questions
How does the Bacon cipher work?▾
Each of the 26 letters maps to a unique 5-bit code using only A and B: A=AAAAA, B=AAAAB, C=AAABA … Z=BAAAB. It is essentially a base-2 encoding.
What was it used for historically?▾
Bacon designed it for steganography — hiding secret messages in plain text by printing letters in two different typefaces (A-type and B-type), invisible to casual readers.
Why does Y share Z's code?▾
The original Bacon cipher had only 24 codes — I/J were combined and U/V were combined, following Latin alphabet conventions. This tool uses distinct codes for all 26 letters.