Vigenère Cipher Tool
Encode or decode Latin-letter puzzle text using a repeating key.
Tool inputs stay in your browser · optional AI search sends your query
Good to know: Repeats a letter key across A–Z, advancing only on letters. Spaces/punctuation are preserved. Historical educational cipher only; not modern encryption or a safe way to protect secrets.
How to use it (step by step)
- 1Type or paste your text into the “Input” box. There is already an example in it so you can see how it works; press Clear to start with your own.
- 2Choose your settings: “Latin-letter key”, “Mode”.
- 3The answer appears right away in the “Result” box. No button needed.
- 4Press Copy and paste the result wherever you need it.
Words to know
- Morse code / cipher
- Old ways of writing messages with codes: Morse uses dots and dashes; a cipher swaps letters by a rule. Fun for puzzles, not for real secrets.
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