Ciphers

Atbash

Mirror the alphabet. A becomes Z, B becomes Y. Hebrew in origin, one key, self-inverse.
create
create("atbash")
family
Reflection
options
none
self-inverse
yes
keyspace
0 (single deterministic mapping)
try it
ciphers atbash "ATTACK AT DAWN"

Each letter maps to its mirror: A to Z, B to Y, M to N. Twice is the identity, so encode and decode are one operation. Case survives, everything else passes through.

const atbash = create("atbash");
atbash.encode("HELLO").text; // "SVOOL"
atbash.encode("Hello, World!").text; // "Svool, Dliow!"
atbash.decode("ZGGZXP ZG WZDM").text; // "ATTACK AT DAWN"

Atbash is the Affine cipher with a = 25 and b = 25. Check it if you don't believe me, the playground is right there.

@agntn/ciphers·MIT license· Classical ciphers, for lessons and puzzles. Not for protecting anything, ever.