Lighthouse : Lighthouse is an open-source, automated tool for improving the quality of web pages. You can run it against any web page, public or requiring authenti...
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
httpbin : Testing an HTTP Library can become difficult sometimes. PostBin.org is fantastic for testing POST requests, but not much else. This exists to cover al...
mobiReady : The mobiReady testing tool evaluates mobile-readiness using industry best practices & standards.
Hurl : Hurl is a command line tool that runs HTTP requests defined in a simple plain text format.
It can chain requests, capture values and evaluate queries ...
an accessibility visualization toolkit that aims to reduce the friction of a11y testing