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

"CrypTool educates PC users about the basics of cryptography in a fascinating way. It allows the exploration of various crypto mechanisms in a very illustrative way. The implementation of ancient algorithms provides an interesting walk through the history of cryptology - ending up with a comprehensive demonstration of all modern implementations."

Sascha Hanke, Microsoft Deutschland GmbH

CrypTool News

New Version of CrypTool — CT 1.4.41 released

A new release of CrypTool 1 was published on March 27, 2018.

This mature version is available in 6 languages (German, English, Spanish, Polish, Serbian, and French). Compared to 1.4.40, it contains many small bug fixes and corrections (especially for functions using Animal, Flash, HTML, and PDF).

Read more ...

New Release of CrypTool — CT 1.4.40 released

A new release of CrypTool 1 was published on September 21, 2017.

This version is available in 6 languages (German, English, Spanish, Polish, Serbian, and French), and it contains many bug fixes and corrections.

Read more ...

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)

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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