Atbash Cipher

How to Use

1. Enter text to encrypt or decrypt
2. Click "Encode / Decode" (Atbash encoding and decoding are the same operation)
3. Click "Copy" to copy the result

How It Works

The Atbash cipher maps each letter to its reverse in the alphabet:

Plain:  A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Cipher: Z Y X W V U T S R Q P O N M L K J I H G F E D C B A

Example: HELLO → SVOOL

常见问题

Where does the name 'Atbash' come from?

Atbash comes from the Hebrew alphabet: Aleph(A)→Tav(T), Beth(B)→Shin(Sh). It first appeared in the Book of Jeremiah in the Bible.

Why is encoding the same as decoding?

Because the mapping is symmetric (A↔Z, B↔Y...). Applying Atbash twice returns the original letter. This property is called an 'involution.'

Is the Atbash cipher secure?

Not at all. Atbash has only one fixed mapping with no key. Anyone can easily decode it. It's used for education and fun only.