Atbash Cipher

Encode or decode text by reversing the alphabet (A-Z).

Plaintext

Note: Atbash replaces each letter with its opposite in the alphabet (A↔Z, B↔Y, etc.). Like ROT13 it is an involution — applying it twice returns the original text.

What Is a Atbash Cipher?

The Atbash Cipher tool replaces each letter with its opposite in the alphabet: A becomes Z, B becomes Y, and so on. It is a simple substitution cipher that appears in historical texts such as the Bible and is an involution — applying it twice returns the original.

How to Use This Atbash Cipher

1
Enter TextType the plaintext or ciphertext.
2
EncodeClick 'Encode' to apply the alphabet reversal.
3
Copy ResultSave the transformed text.

Frequently Asked Questions

Reversing the alphabet twice brings every letter back to its start, so encoding and decoding are the same operation.

Historically for secret writing; today mostly in puzzles, games, and education. It provides no real security.

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