A tool for solving single-letter substitution cryptograms. Encrypted text must be input as uppercase A-Z characters; any other characters (including punctuation and spaces) will be left as-is.
- Clear will reset the map.
- ROT13 shifts each letter by 13 (a->n, b->0, etc.).
- aX+b implements a more general linear substitution, where under the standard numbering a=0...z=25, each number x is sent to ax+b (mod 26).
- ROT13 corresponds to a=1, b=13.
- The Caesar cipher corresponds to a=1, b=3.
a:
b: