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Atbash Cipher — Reverse-Alphabet Encode/Decode

Atbash maps each letter to its mirror position in the reversed alphabet (A↔Z, B↔Y, and so on) — one of the oldest known ciphers, originally used with the Hebrew alphabet and referenced in some interpretations of biblical text. It is its own exact inverse: encoding a message twice returns the original.

How to use Atbash Cipher

1. Paste your text.
2. Read the Atbash result instantly.
3. Run it through again to get back the original text.

Frequently asked questions

Why is Atbash its own inverse?

Because the mapping is symmetric around the alphabet's midpoint — A maps to Z and Z maps to A, so applying the same transformation twice returns every letter to its starting position.

Where does Atbash come from historically?

It originated with the Hebrew alphabet and is one of the oldest documented substitution ciphers, with some biblical texts cited by scholars as containing possible Atbash-encoded wordplay.

Is Atbash secure for anything today?

No — with a fixed, keyless mapping, it is trivially reversible and offers no real security, useful only as a historical curiosity or a simple puzzle mechanic.

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Also searched for: atbash cipher encoder decoder · reverse alphabet cipher online · hebrew atbash cipher tool

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