American Cryptogram Association

From Wikipedia, the free encyclopedia
American Cryptogram Association
FormationSept. 1, 1930; 93 years ago (Sept. 1, 1930)
DARING FLAIR[citation needed]

The American Cryptogram Association (ACA) is an American non-profit organization devoted to the hobby of cryptography, with an emphasis on types of codes, ciphers, and cryptograms that can be solved either with pencil and paper, or with computers, but not computer-only systems.


The ACA was formed on September 1, 1930. Initially the primary interest was in monoalphabetic substitution ciphers (also known as "single alphabet" or "Aristocrat" puzzles), but this has since extended to dozens of different systems, such as Playfair, autokey, transposition, and Vigenère ciphers.

Since some of its members had belonged to the “National Puzzlers' League”, some of the NPL terminology ("nom," "Krewe," etc.) is also used in the ACA.[1]

Publications and activities[edit]

The association has a collection of books and articles on cryptography and related subjects in the library at Kent State University.

An annual convention takes place in late August or early September. Recent conventions have been held in Bletchley Park and Fort Lauderdale, Florida.

There is also a regular journal called “The Cryptogram”, which first appeared in February, 1932, and has grown to a 28-page bimonthly periodical which includes articles and challenge ciphers.

Notable members[edit]


External links[edit]