Atbash Cipher Encoder and Decoder
Encode and decode text with the Atbash cipher, which reverses the alphabet so A becomes Z. Supports Latin, Greek and Hebrew letters, free and in your browser.
How to use Atbash Cipher
- 1Type or paste your text into the box.
- 2Choose Latin, Greek or Hebrew, and decide whether to keep case and punctuation.
- 3Copy the result. Run the result through the tool again to get your original text back.
What makes it better
- Reverses the alphabet: A to Z, B to Y, and so on
- Same operation encodes and decodes
- Latin, Greek and Hebrew alphabets
- Keeps capitals, spaces, punctuation and emoji, or outputs upper-case letters only
About Atbash Cipher
The Atbash cipher is a substitution that mirrors the alphabet: the first letter becomes the last, the second becomes the second to last, and so on. It has no key and is symmetric, so the same operation encodes and decodes. This tool works live in your browser with Latin, Greek or Hebrew letters.
Common uses
- Decode an Atbash clue in a puzzle, novel, game or geocache.
- Explore the historical cipher that appears in Hebrew texts, where it gives Sheshach for Babel.
- Teach substitution ciphers with an example that needs no key.
- Generate a quick, light obfuscation of a spoiler or answer.
Example
Input
Hello
Result
Svool
Good to know
- Classical ciphers offer no real security: a computer breaks them in milliseconds. For real encryption use AES-256 (see AES Encrypt).
- Atbash has a single fixed substitution, so it protects nothing against anyone who recognizes it. It is also its own inverse.
- Greek final sigma and Hebrew final-form letters, and accented Greek letters, are not changed because they have no unique mirror position; only the base letters are mapped.
Atbash Cipher FAQ
What is the Atbash cipher?
Atbash is a monoalphabetic substitution cipher that replaces the first letter of the alphabet with the last, the second with the second to last, and so on. The name comes from the Hebrew letters aleph, tav, bet and shin.
How do I decode Atbash?
Run the Atbash text through the tool again. Mirroring the alphabet twice returns each letter to where it started, so encoding and decoding are the same step.
What is Atbash of the word Hello?
Hello becomes Svool: H maps to S, e to v, l to o and o to l. Capitals stay capitals when Keep case is on.
How is Atbash different from ROT13 and Caesar?
Caesar and ROT13 slide the alphabet by a number of places, while Atbash flips it end to end. Atbash therefore has no key to choose, which makes it easier to spot than a Caesar shift.