How do I decode a Bacon cipher?

Choose Decode and paste the A/B groups (0/1 also works). The tool reads each group of five symbols back into a letter.

Which Bacon variant does this use?

It uses the modern 26-letter version, giving every letter its own distinct code rather than sharing codes for I/J and U/V as the original 24-letter table did.

Is it free and private?

Yes — it runs entirely in your browser with no sign-up, and nothing you type is uploaded.

Bacon Cipher Encoder & Decoder

Encode and decode the Bacon (Baconian) cipher, which turns each letter into a group of five A/B symbols — a classic way to hide messages.

Encoded

AABBB AABAA ABABB ABABB ABBBA

What is the Bacon cipher?

The Bacon cipher (or Baconian cipher), devised by Francis Bacon around 1605, encodes each letter as a group of five symbols drawn from just two options — here shown as A and B. Its clever twist is that the A/B pattern can be hidden inside ordinary text using two typefaces or styles.

How to use it

Choose Encode or Decode.
Type your message, or paste A/B groups (0/1 also works) to decode.
Tap Copy to save the result.

How the Bacon cipher works

Each letter maps to a fixed five-symbol code, giving 32 possible patterns — more than enough for 26 letters. This tool uses the modern 26-letter version, so every letter has its own distinct code rather than sharing one for I/J and U/V as the original table did.

Where it is used

Beyond puzzles and cryptography lessons, the Bacon cipher is a classic example of steganography — hiding the very existence of a message inside something that looks innocent.

More codes and ciphers

Explore the rest of the family: the Caesar Cipher, Atbash, Vigenère, and A1Z26. For other encodings, try the Morse Code Translator and the Binary Translator.

Free and private

This Bacon cipher tool runs entirely in your browser — free, with no sign-up, and nothing you type is uploaded or stored.

Frequently asked questions

What is the Bacon cipher?: The Baconian cipher, devised by Francis Bacon, encodes each letter as a unique group of five A/B symbols (for example A = AAAAA, B = AAAAB). It can be hidden inside other text using two typefaces or styles.
How do I decode a Bacon cipher?: Choose Decode and paste the A/B groups (0/1 also works). The tool reads each group of five symbols back into a letter.
Which Bacon variant does this use?: It uses the modern 26-letter version, giving every letter its own distinct code rather than sharing codes for I/J and U/V as the original 24-letter table did.
Is it free and private?: Yes — it runs entirely in your browser with no sign-up, and nothing you type is uploaded.