How to Check Your Browser Security

Qualys BrowserCheck 

Qualys BrowserCheck is a free tool that scans your browser and its plugins to find potential vulnerabilities and security holes and help you fix them.

https://browsercheck.qualys.com/

Browser Scope

Browserscope is a community-driven project for profiling web browsers. The goals are to foster innovation by tracking browser functionality and to be a resource for web developers.

http://www.browserscope.org/security/test

Panopticlick

Panopticlick checks if your browser’s configuration is unique. The more unique your browser, the less easily it could be tracked. Web tracking is a privacy risk for users.

http://panopticlick.eff.org/