mitmproxy : mitmproxy is your swiss-army knife for debugging, testing, privacy measurements, and penetration testing. It can be used to intercept, inspect, modify...
webhint : webhint is a linting tool that will help you with your site's accessibility, speed, security and more, by checking your code for best practices and co...
The Big List of Naughty Strings : The Big List of Naughty Strings is a list of strings which have a high probability of causing issues when used as user-input data.
badssl.com : Memorable site for testing clients against bad SSL configs.
OpenVAS : OpenVAS is a full-featured vulnerability scanner. Its capabilities include unauthenticated testing, authenticated testing, various high level and low ...
This free online service performs a deep analysis of the configuration of any SSL web server on the public Internet.