Websites

  • Klaus‘s Cipherbrain blog: Established in 2013, originally in German and then switched to English in 2017, this blog contains over a thousand reports on codebreaking and historical encryption. There is also a very active community of blog readers who enthusiastically engage whenever a new blog post appears.
  • Elonka’s website: Contains, among other things, Elonka’s list of Famous Unsolved Codes and Ciphers. Her website is also considered the gold standard for information about the CIA’s encrypted sculpture Kryptos, as well as containing information about other famous solved cryptograms such as the Friedman tombstone, the Smithy Code, and the Cyrillic Projector. Also includes a tutorial on how Elonka solved a hacker challenge (the PhreakNIC v3.0 Code) in 1999, which was the start of her codebreaking career.
  • Cipher Mysteries: Nick Pelling, a London-based codebreaking expert, prolific author, and researcher, operates this exhaustive website including information about the Voynich Manuscript and other encryption mysteries. He has hundreds of blog articles about topics from the latest purported Voynich solutions, to an analysis review of research on the Somerton Man, to Masonic ciphers.
  • MysteryTwister C3: MTC3 is a website run by a group of German crypto-enthusiasts, including a few who are behind the CrypTool utility. The site has over 300 crypto puzzle challenges submitted from all over the world.
  • CrypTool website: CrypTool 2 is a free crypto learning program, developed by an international team headed by Bernhard Esslinger. Among other things, it supports many helpful codebreaking tools. The CrypTool project also offers further e-learning programs for cryptography and cryptanalysis, such as CrypTool 1, JavaCrypTool, and CrypTool-Online. Th CrypTool website not only provides the CrypTool software for download, but also contains a great deal of interesting information about cryptography and codebreaking. In addition, there’s a related YouTube channel named “CRYPTOOL 2 – Cryptography for Everybody” operated by CrypTool developer Nils Kopal.
  • Cipher Tools: Cipher Tools is a large collection of classical cryptanalysis tools operated by Tyler Akins.
  • dCode: The website dCode, operated by an anonymous group of crypto-enthusiasts, provides numerous helpful codebreaking and statistics tools.
  • Satoshi Tomokiyo’s Cryptiana website: Satoshi Tomokiyo from Tokyo, Japan, operates this great website about historical encryption techniques, old cryptograms, and solution methods.
  • Cipher History is a comprehensive website about vintage cryptography, operated by cipher-machine collector Ralph Simpson.
  • Website of the American Cryptogram Association (ACA): The ACA is an organization dedicated to promoting the hobby and art of codebreaking. Their website provides loads of interesting information. They run an annual convention and publish a bimonthly newsletter that contains a variety of cryptograms, along with a competition and points system for solving them.
  • Kryptos discussion group: Founded by Elonka and the late Gary Warzin, originally on Yahoogroups and then moved to groups.io. As of 2020, co-moderated by Elonka, Chris Hanson, and Larry McElhiney.
  • DECODE: This is a website about historical ciphers operated by scientists from the University of Uppsala, Sweden, which also includes a large database of unsolved cryptograms.
  • Portal of Historical Ciphers: A website about historical ciphers operated by Eugen Antal  from Slovakia, which features a database of unsolved cryptograms.
  • Cryptograms & Classical Ciphers Facebook group: Bart Wenmeckers, a New Zealand-based codebreaking expert, hosts this Facebook group.
  • Christos’ Military and Intelligence Corner: Operated by Greek crypto history and intelligence expert Christos Triantafyllopoulos, this blog covers historical cryptology, along with military and intelligence topics.
  • Dave Oranchak’s page: Run by Dave Oranchak from Roanoke, Virginia, this page mainly covers the Zodiac Killer and his cryptograms.
  • Cryptomuseum: A comprehensive website about cipher machines and crypto devices, operated by Dutch experts Paul Reuvers and Marc Simons.
  • Schneier on Security: Bruce Schneier has the gold standard in blogs about modern crypto systems, along with his monthly newsletter “Crypto-Gram”. He also occasionally covers information about classical ciphers.
  • La Crittografia da Atbash a RSA: An Italian site operated by codebreaking expert Paolo Bonavoglia.
  • Benedek Láng’s website, “Rejtjelek, kódok, titkosírások” (“Codes, Ciphers, and Cryptograms”): If you happen to speak Hungarian (or if you use Google Translate or the German site DeepL), this page provides many interesting facts about codebreaking.
  • Katkryptolog: An interesting crypto history and codebreaking blog, partially written in Slovak by Hans Jahr.