I needed this today ( two different Rot ciphers/cyphers ), so I decided to go ahead with Rot1 - Rot25 and Rot47. Example (Run from SciTe to see output): #include "cipherRot.au3" Global $gs_Original = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" Global $gs_Encode = "" For $i = 1 To 25 ; notice decode param used with 1-4, 6-12, 14-17, 19-25 $gs_Encode = _cipher_Rot($gs_Original, $i) ConsoleWrite("Rot" & $i & @TAB & "Encode: " & $gs_Encode & @CRL