Bacon cipher decoder
Turn A and B symbols back into text to solve Bacon cipher puzzles. It is a puzzle cipher, not a security tool.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter bacon code and alphabet version.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
Every 5 symbols are read as a binary number (A = 0, B = 1), which is the letter number in the chosen alphabet (A = 0). Spaces do not matter; / separates words.
Example
Inputs: Alphabet version = Original 24 letters (I=J, U=V). Result: Decoded text: HELLO; Letters: 5.
AABBB AABAA ABABA ABABA ABBAB
HELLO
Limits and caveats
- This is a puzzle and teaching cipher that is easy to break, so never use it to protect passwords or sensitive data.
- In the original version I stands for J and U for V, so read words in context.
- It does not read codes hidden in two-typeface cover text; you need the A and B written out.
Questions about this tool
How do I know which alphabet version to use?
Groups like BBAAB or BBAAA point to the 26-letter version. Try both and keep the one that reads well.
Do I need spaces between groups?
No. The tool reads every 5 symbols in a row as one letter; spaces are only for readability.
Why does it show IAM instead of JAM?
In Bacon's original alphabet I and J share a code, so the tool always shows I.