Atbash Cipher (Encode & Decode)

What does this tool do?

Atbash Cipher is a classic substitution cipher that swaps each letter for its mirror in the alphabet: A becomes Z, B becomes Y, C becomes X, and so on. It shows the result as you type, and because the same operation also decodes, you handle both encryption and decryption in one place. It is ideal for puzzle fans, students, and anyone learning the basics of cryptography.

How to use it

1. Enter the text you want to encode or decode.
2. The conversion happens automatically.
3. Copy the result and use it safely.

What symmetric means here

Atbash is its own inverse: apply the same mapping twice and you return to the original text. That is why there is no separate encode and decode button; pasting ciphertext into the same box gives you the plaintext. For example, "HELLO" produces "SVOOL", and entering "SVOOL" returns "HELLO". This property makes it very practical for teaching the concept and for verifying results quickly.

Non-letter characters are preserved

The tool only transforms letters of the English alphabet (A-Z and a-z), and letter case is kept intact. Spaces, digits, punctuation, and other symbols pass through unchanged. This keeps sentence structure and layout readable while only the letters are scrambled. Accented or non-Latin characters that fall outside A-Z are left exactly as they are, so they reappear untouched in the output.

Frequently asked questions