Welcome to the Randomness Testing Guide. This website is a beginner's guide to randomness testing with a focus on simplicity and explainability. Try it out below!
In the late 1990s, the National Institute of Standards and Technology (NIST) began development of the Advanced Encryption Standard (AES). Today, AES is used by many VPN providers as part of the OpenVPN standard. It is also used by default by 7-zip for encrypting files. You can even see AES referenced in the "Security" tab of the Chrome developer tools on websites using HTTPS.
To ensure that the AES algorithm didn't have any weaknesses, NIST developed a battery of statistical tests to determine whether AES output could be considered "random". Although their tests were very detailed, third-party researchers pointed out many issues in the following years. These issues mostly arose from how complex the tests were. The goal of this guide is to simplify randomness testing and make it more accessible for hobbyists.