The Atbash Cipher is an incredibly simplistic cipher, where each letter in the alphabet is replaced with the "opposite" letter in the alphabet. It is considered a simple substitution cipher - simple substitution ciphers are described as ciphers where single letters are replaced with other single letters. The Atbash cipher was originally made to work with the Hebrew alphabet, but can be modified to work with any alphabet with a limited amount of characters.
Encoding for the Atbash cipher is incredibly simple. Replace each letter in the plaintext - the message to be encoded - with the letter in the alphabet directly opposite of it. For instance, the letter A is replaced with Z, B is replaced with Y, etc. Use the table to help you in encoding a message.
Decoding Atbash is also incredibly easy, simply use the same method of encryption to decrypt the message.
Breaking the Atbash is relatively trivial. If you know the Atbash cipher has been used, you can easily decrypt the message. If you don't know that Atbash has been used, try to decrypt the first few letters. If they make sense, continue to decrypt the message. If they don't, then Atbash hasn't been used. This is why we consider Atbash an incredibly weak cryptographic method, since it is easily broken in a short amount of time. It provides little to no security.
Plaintext: 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
Ciphertext: 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
Plaintext: CRYPTOLOGY IS COOL
Ciphertext: XIBKGLOLTB RH XLLO
Example 1: Decipher GSV JFRXP YILDM ULC QFNKH LEVI GSV OZAB WLT Example 2: Decipher BLF XVIGZRMOB ZIV WVGVINRMVW Example 3: Encipher THE ATTACK BEGINS ON THE BEACH AT NOON Example 4: Encipher THE ATBASH CIPHER IS SIMPLE Paragraph: DecipherGDVOEV ELRXVH DVIV HSLFGRMT RM ZMTVI, ZMW GSVB DVIV ZOO ZORPV. ML JFVHGRLM, MLD, DSZG SZW SZKKVMVW GL GSV UZXVH LU GSV KRTH.
GSV XIVZGFIVH LFGHRWV OLLPVW UILN KRT GL NZM, ZMW UILN NZM GL KRT, ZMW UILN KRT GL NZM ZTZRM;
YFG ZOIVZWB RG DZH RNKLHHRYOV GL HZB DSRXS DZH DSRXS.