SubstitutionDifficulty: Easy
Atbash
The alphabet flipped like a mirror: A becomes Z, B becomes Y. No key, no settings, and decoding is the same as encoding.
Try it
27 characters
Result · Atbash
Hvxivg nvhhztv uli gsv xofy
How it works
- 1Write the alphabet and right under it the same alphabet backwards: Z sits under A, Y under B, X under C.
- 2Find each letter of your message in the top row and write down the one beneath it.
- 3It is a mirror: the first letter swaps with the last, the second with the second to last. A becomes Z and Z becomes A.
- 4Decoding is exactly the same - mirror the secret text once more to read it.
Example
Hello world
Svool dliow
Did you know
The name comes from the Hebrew alphabet: the first letter (aleph) swaps with the last (taw), the second (bet) with the second to last (shin) - A-T-B-Sh. The cipher already appears in the Bible, in the Book of Jeremiah, where the word Sheshach really stands for Babylon. It is one of the oldest known ciphers.
Try to decode
This message is encrypted with Atbash using the default settings:
GSV GIVZHFIV RH FMWVI GSV LZP
Hint
Mirror alphabet: A is Z, B is Y, C is X. Start from the other end.
Show solution
THE TREASURE IS UNDER THE OAK
More ciphers in this category
- Caesar cipherEvery letter moves a fixed number of places along the alphabet. The most famous cipher in the world and a perfect first step.
- Vigenère cipherA Caesar cipher with a password: each letter shifts by a different amount set by the keyword. Much tougher than plain shifting.
- Polybius squareLetters in a 5x5 grid, each written as a pair of numbers: row and column. You can tap it, flash it or clap it.
- ROT13A Caesar cipher with a shift of 13: the same steps encode and decode. No settings, just one click.