Bacon Cipher
Encode text into Baconian five-letter A/B groups and back.
A five-bit letter code
Francis Bacon’s cipher predates binary but works just like it: each letter becomes a group of five symbols, here written as As and Bs. It is one of the earliest examples of a binary encoding.
The word HELLO encodes to five groups of five letters. In its classic use the A/B pattern is hidden in the styling of an innocent-looking message; this tool works with the raw code so you can see the structure.
Historical and private
Encoding runs in your browser, so your text is never uploaded.
Frequently Asked Questions
What is the Bacon cipher?
A cipher devised by Francis Bacon that encodes each letter as a group of five As and Bs, like a five-bit binary code.
How is it usually hidden?
Traditionally the A/B pattern is concealed in two typefaces or cases of an ordinary message — this tool shows the raw A/B code.
Which alphabet is used?
The distinct 26-letter version, so every letter has its own unique code.
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