whoiswp
Detect what theme and plugins that website is using
4 Alternatives To whoiswp
Similar Tech
SimilarTech offers a Sales Insights platform which helps companies uncover their ideal market by crawling the sourcecode of over 300M sites.
Wappalyzer
Follow ElbertF on GitHub and watch them build beautiful projects.
What CMS
WhatCMS.org looks at a variety of factors within a webpage to determine what CMS a website is using.
WhatRuns
Extension that helps you identify technologies used on any website at the click of a button.