The Affine cipher is a monoalphabetic substitution cipher and it can be the exact same as a standard Caesarian shift when
a is 1. Mathematically, it is represented as . Decryption is a slightly different formula, .
- - The example Wikipedia uses to show off the cipher.
To encode something, you need to pick the
a and it must be coprime with the length of the alphabet, which is the
m value. To make this easier, I have the (+) and (-) buttons to change the A to the next higher or lower coprime number.