General: CrypTool is a free, open-source e-learning application, used worldwide in the implementation and analysis of cryptographic algorithms. It supports both contemporary teaching methods at schools and universities as well as awareness training for employees and civil servants.

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This software is working with the most used cryptographic algorithms. You can choose, between classic ciphers, and modern ciphers.
You can analyse your ciphers, see how these works and more. And finally, it’s total free to use!

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