SeeJS

SeeJS allows you to visualize the javascript code behind any web page.

To use this extension, navigate to the web page of your choosing and click on the blue circle icon at the top of your browser. Wait for the extension to fetch all the javascript source files defined on that page. Once loaded, each script is listed and color coded by size. You can select which files and inline scripts to visualize. By default all source files are selected but not inline scripts. Click GO to parse the code and build the visualization. Note that sites with a large code base such as Facebook can take up to 2 minutes to process and will create a slow and clunky visualization. While processing, the extension icon will be displayed in red.

Once code processing is complete, a new tab will open with the visualization. Each circle represents a function. White circles are anonymous functions while named functions are color coded by their source file. Circles are sized based on the size of the represented function. Hovering over a circle will display the function name in a tooltip. Zoom and pan to explore the visualization.

Click on the 'Code' link in the top nav bar to open a javascript editor to see the unminified source code. Clicking on a circle in the visualization will display that function's source code in the editor. Conversely, clicking on a function in the editor will highlight that function in the visualization.

Enjoy!