Atbash Cipher | Encoder and Decoder Online

Atbash cipher encoder and decoder that mirrors the alphabet, A to Z and B to Y, with the full mapping table shown. Keeps case, digits and punctuation. Free.

Also known as: atbash cipher · atbash cipher decoder · atbash translator · atbash cipher online · reverse alphabet cipher · mirror alphabet code · hebrew atbash cipher · a to z reverse cipher

encoding and decoding tools

encryption tools

text tools

encoders

Text Input

Atbash Output

Atbash Mapping Table

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

Each letter swaps with its mirror: A and Z, B and Y, M and N. Highlighted columns are letters in your text. Because the mapping is symmetric, the same step encodes and decodes, and digits, spaces and punctuation pass through unchanged.

About Atbash Cipher

The Atbash cipher is used in puzzles, escape rooms and classroom cryptography to hide a message by mirroring the alphabet, so A becomes Z and B becomes Y. This tool encodes and decodes Atbash as you type, keeps upper and lower case, and shows the full mapping table with the letters in your text highlighted.

Key Features

Live Atbash encoding and decoding in one step, since the cipher is its own inverse
Keeps upper and lower case, digits, spaces and punctuation exactly where they were
A full A to Z mapping table that highlights the letters your message uses
Use Output as Input to check a round trip without retyping
File upload and download for longer passages, processed in your browser

Use Cases

Setting or solving a clue for an escape room, scavenger hunt or geocache
Decoding the Atbash messages hidden in shows like Gravity Falls
Teaching how a fixed substitution cipher works before Caesar and Vigenere
Checking a CTF string that looks like reversed-alphabet text
Studying the Hebrew origins of Atbash in biblical texts such as Jeremiah

Supported Formats

Plain text

TXT files

Markdown

Related Keywords

atbash cipher

atbash cipher decoder

atbash translator

atbash cipher online

reverse alphabet cipher

mirror alphabet code

hebrew atbash cipher

a to z reverse cipher

How do you decode an Atbash cipher?

Replace each letter with the one in the mirror position of the alphabet: A with Z, B with Y, C with X, down to M and N. Decoding is the same operation as encoding, so you run the ciphertext through Atbash once and the plain text comes back. Atbash has no key, which also means it offers no security: anyone who suspects it can read the message in seconds.

Privacy & Security

All processing happens locally in your browser. Your data never leaves your computer, ensuring complete privacy and security.

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Frequently asked questions

What is Atbash Cipher used for?

Atbash cipher encoder and decoder that mirrors the alphabet, A to Z and B to Y, with the full mapping table shown. Keeps case, digits and punctuation. Free.

Is Atbash Cipher free to use?

Yes. Atbash Cipher is completely free with no usage limits, and there is no paid tier required to use it.

Do I need an account to use Atbash Cipher?

No. Atbash Cipher works immediately in your browser with no signup, login, or email address required.

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