What is CrypTool 1?

CrypTool 1 (CT1) is an open-source Windows program for cryptography and cryptanalysis. It’s the most widespread 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 workflow.

What is JCrypTool?

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

What is CrypTool-Online?

CrypTool-Online (CTO) runs in a browser and provides a variety of encryption and cryptanalysis methods including illustrated examples and tools like password generator and password meter.

What is MysteryTwister?

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

Welcome to the CrypTool Portal

The CrypTool Portal (CTP) is the starting page of the CrypTool project. Its aim is to raise awareness and interest in encryption techniques for everyone.

The CT project develops the world's most-widespread free e-learning programs in the area of cryptography and cryptanalysis. All learning programs in the CT project are open source and available for free.

E-Learning Platforms

Crypto Challenge Contest

Want to participate?

Volunteers, especially programmers, and students planning to write their thesis in the area of cryptography, are always welcome to join in the further development of the CrypTool project. You will experience project management in a distributed open-source project.

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General News

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CrypTool 2 Release 2021.1 published

In May 2021, we published the release "2021.1", which is the first one this year and a major functional update. The...

Read more ... 05/12/21
JCrypTool version 1.0 released

Version 1.0 of JCrypTool was released today, November 30th, 2020. It is intended for beginners and experts in cryptog...

Read more ... 11/30/20
CrypTool website completely renewed

In the course of 2020, the CrypTool portal was comprehensively renewed once again. The website at www.cryptool.o...

Read more ... 10/30/20