BuiltWith.com is a website that shows you all the information about the technology a website uses. For instance, it gives you the facts about the site’s web servers. It also displays information about the code used on the website, for example, the HTML version and whether it uses PHP and/or Javascript and/or CSS. Other information shown is the encoding format, the use of a Content Management System (such as Wordpress), and the Analytics and Tracking tool (such as Google Analytics).
A great feature of BuiltWith.com is its trends and statistics section. In the trends section, you can see which technologies have gained market share recently, and which ones have lost importance. In the statistics section, you can see the total usage of the top 20 technologies in every category. In the widget category, for example, Wordpress is clearly first with over 2.3 million websites using it, whereas the second most-used widget is featured on only 1.1 million websites (AddThis).
BuiltWith.com is free and works in a browser. There is also a Google Chrome Extension available that lets you directly look up a website.
