What is CrypTool 1

CrypTool 1 (CT1) is an open-source Windows program for cryptography and cryptanalysis. It’s the most wide-spreaded e-learning software of its kind.

What is CrypTool 2?

CrypTool 2 (CT2) is an open-source program offering an innovative visual programming GUI to experiment with cryptographic procedures and to animate their cascades.

What is JCrypTool?

JCrypTool (JCT) is an open-source e-learning platform, allowing to experiment comprehensively with cryptography on Linux, MAC OS X, and Windows.

What is CrypTool-Online?

CrypTool-Online (CTO) runs in a browser and provides a huge variety of encryption methods and analysis tools including many illustrated examples.

What is MysteryTwister C3?

MysteryTwister C3 (MTC3) is an international Crypto Cipher Contest offering a broad variety of challenges, a moderated forum and an ongoing hall-of-fame.

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Land der Ideen - Statements

"In the field of educating students or IT-professionals, this tool gives you much support and wonderful help to increase their knowledge. Beside of theoretical background, it gives the possibility to consolidate the knowledge by practical experiences. Only this mixture of theory and practice leads to real understanding."

Prof. Dr. sc. nat. Christoph Meinel, Uni Trier

CrypTool News

CryptoPrograms with Online Analyzers

The website CryptoPrograms http://www.cryptoprograms.com is dedicated to create and solve classical ciphers online.
New on this site are analyzers for solving classical ciphers without any knowledge of the keyword and, in many cases, the key length. Routines for solving around 40 cipher types are provided.
(2017-07-30)

Release Candidate 8 available

JCrypTool 1.0.0 Release Candidate 8 is available on our download page.
Read more ...

Join the #CSCG

The Cyber Security Challenge Germany (CSCG) is the German hacking competition for pupils and students. There are 12 online challenges starting on May 2nd, 2016. The juveniles have to solve different IT-Security tasks till August.
Read more ...

New Update Site

The JCrypTool update site moved to http://www.cryptool.org/jct/update. This URL must be updated in JCrypTool manually if you are using a release older than release candidate 5a.
  1. Launch JCrypTool and open the preferences via Window - Preferences
  2. Expand the Install/ Update section and select Available Software Sites
  3. There should be one entry with the location http://www.cryptool.org/jcryptool/update
  4. Select this entry and click Edit
  5. Replace the location link with the new update site URL http://www.cryptool.org/jct/update
  6. You can give the update site a name optionally (in case this wasn't filled automatically)
  7. Click OK to close the dialog and OK to close the preferences
That's it. Now you can use the update manager again.

In case you are already using release candidate 5a (RC5a) you do not have to update the URL.
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