# Atbash Cipher > Encode and decode the Atbash cipher, which swaps each letter with its mirror (A↔Z, B↔Y), with the alphabet chart, step-by-step working and examples. - Page: https://linguaholic.com/tools/atbash-cipher/ - Type: free online tool (Converters & translators), no sign-up, runs in the browser - Publisher: Linguaholic (https://linguaholic.com/), made by Marcel Iseli - Last updated: October 3, 2026 - Open it pre-filled: https://linguaholic.com/tools/atbash-cipher/?text=Svool+Dliow - `text`: text to convert (Atbash encodes and decodes with the same operation) (for example `Svool Dliow`) - `open`: open a section: crack (Atbash plus all 312 affine and Caesar keys ranked), steps (mirrored alphabet and worked letters), frequency (letter counts) or identify (which cipher is this?) (for example `steps`) ## What is the Atbash cipher? The **Atbash cipher** swaps each letter with its mirror image in the alphabet: the first letter with the last, the second with the second to last, and so on. A becomes Z, B becomes Y, C becomes X, and M and N swap in the middle. Nothing else is involved: there is no key and no number to choose. Because the swap works both ways, **encoding and decoding are the same step**, so this tool has no Encode or Decode switch. Atbash began as a cipher for the Hebrew alphabet and is one of the oldest known letter ciphers. Today it turns up in puzzle books, escape rooms, treasure hunts and television mysteries, often as the first code a solver learns. ## How to use the Atbash cipher decoder and translator 1. Type or paste your text. The Atbash version appears below as you type. 2. To decode, paste Atbash text in the same box: the result is the original message. Capital and small letters keep their case; spaces, digits and punctuation do not change. 3. Press **Copy**, or **Use as input** to flip the result back and check it. Open **Step by step** to see the mirrored alphabet and the working for each letter, or **Letter frequencies** to compare a message’s letters with English. If a text is not Atbash after all, **Crack it** tries all 312 single-alphabet keys of the affine cipher (every Caesar shift is among them) and **Which cipher is this?** suggests what else it might be. A link such as `?text=Svool` opens the tool already filled in. ## Frequently asked questions **What is the Atbash cipher?** A cipher that swaps every letter with its mirror in the alphabet: A with Z, B with Y, C with X and so on, up to M with N. It has no key. **How do you decode the Atbash cipher?** Apply Atbash again. Because each letter swaps with its partner, the same step that encodes a message also decodes it. Paste the code into the tool and read the result. **What does HELLO look like in Atbash?** HELLO becomes SVOOL: H and S, E and V, L and O are mirror pairs. **What is the Atbash formula?** With A = 0 to Z = 25, the Atbash letter is 25 minus the letter's number. Counting from A = 1, it is 27 minus the number. **Where does the name Atbash come from?** From the Hebrew alphabet: aleph, the first letter, swaps with tav, the last, and bet, the second, swaps with shin, the second to last. Aleph-tav-bet-shin gives at-bash. **Is Atbash in the Bible?** Yes. In the Book of Jeremiah, Sheshach (25:26 and 51:41) is the Atbash form of Babel, and Leb Kamai (51:1) is the Atbash form of Kasdim, the Chaldeans. **Is Atbash the same as ROT13?** No. Both decode themselves, but ROT13 turns the alphabet halfway round (A to N), while Atbash mirrors it (A to Z). They pair different letters. **Does Atbash change numbers and punctuation?** No. Only the letters A to Z are swapped. Digits, spaces and punctuation stay the same, and letters keep their case. **Can the Atbash cipher be cracked?** There is nothing to crack, because it has no key: anyone who suspects Atbash can read the message at once. If the result is not English, the tool's Crack it section tries every Caesar and affine key instead. ## Data sources The code breaker's English letter frequencies and word checks come from Linguaholic’s English dictionary, built from the open ENABLE and SCOWL word lists. Licenses and notices: https://linguaholic.com/tools/data/dict/v1/NOTICE.txt ## Related tools - [ROT13](https://linguaholic.com/tools/rot13/): Decode and encode ROT13 instantly (the same step does both), switch to ROT5, ROT18 or ROT47, or try every rotation when it is not ROT13. - [Caesar Cipher](https://linguaholic.com/tools/caesar-cipher/): Encode and decode the Caesar shift cipher with any shift from 1 to 25, or crack a message without the key: every shift is tried and ranked for you. - [Affine Cipher](https://linguaholic.com/tools/affine-cipher/): Encode and decode the affine cipher with keys a and b, see the arithmetic for every letter, or crack a message by trying all 312 keys. - [Substitution Cipher](https://linguaholic.com/tools/substitution-cipher/): Encode and decode with any cipher alphabet or keyword, or paste a cryptogram and let the solver crack it; then fix any letter yourself. - [A1Z26 Cipher](https://linguaholic.com/tools/a1z26-cipher/): Decode and encode the A1Z26 cipher, where A=1, B=2 and Z=26: letters to numbers and numbers to letters, with a full chart and puzzle tips. - [Morse Code Translator](https://linguaholic.com/tools/morse-code-translator/): Translate text to Morse code and decode it back, hear it as adjustable-speed sound with a visual flasher, and read the full Morse alphabet, number, and punctuation chart.