The American Cryptogram Association
The American Cryptogram Association (ACA) is a non-profit organization dedicated to promoting the hobby and art of cryptanalysis -- that is, learning to break ciphers.
Presenters Wanted for 2021 Convention – Share your knowledge of ciphers – either onsite or from the comfort of your own home! Contact vicepresident (at) cryptogram (dot) org with questions or if you are interested.

MA2021 Mailing – The Cryptogram was mailed on time. If you have not received your copy, patience is appreciated. Mail service world-wide is still slow.

PayPal If you wish to use PayPal for paying your ACA dues or ACA For Sale items, please refer to the instructions on the membership page.

Free Web App. The ACA’s “Solve a Cipher!” program is now available as a free web app under the Resources tab. To access it, click HERE.

Tutorials for Sample Issue We now have tutorial solutions for all the ciphers in the free Sample Issue of The Cryptogram. Get your solving effort started with a nudge or follow along to see the complete solution of the cipher. It’s like looking over the shoulder of a friend solving a cipher.

THE RAT has upgraded his Conmaker program by adding the following cipher types in the “More Types” menu: CONDI, Nicodemus, Nihilist Substitution, Numbered Key, Phillips, Route, Sequence. The format of the program is slightly smaller and some minor error corrections and cosmetic changes were made. It is designed for Windows users to easily create and submit cons to the ACA column editors. If interested, go to the Members Area / Downloads and get your copy.