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...
Diagnostic.css : Diagnostic.css is a stylesheet which allows the user to test for common errors in a page's markup.
Also : https://github.com/karlgroves/diagnostic.css
aXe : Automated tool to find Accessibility defects on your web site by using the aXe Chrome extension. Drop the aXe on your accessibility defects! We believ...
Nikto2 : Nikto is an Open Source (GPL) web server scanner which performs comprehensive tests against web servers for multiple items, including over 6500 potent...
Subgraph Vega : Vega is an open source platform to test the security of web applications. Vega can help you find and validate SQL Injections, Cross-Site Scripting (XS...
Monitor the accessibility of your websites with pa11y-dashboard, and protect against accessibility errors creeping into your codebase.