Icons of the Web

A large-scale scan of the top million web sites (per Alexa traffic data) was performed in early 2010 using the Nmap Security Scanner and its scripting engine.

Each site's icon was retrieved by first parsing the HTML for a link tag and then falling back to /favicon.ico if that failed. 328,427 unique icons were collected, of which 288,945 were proper images. The remaining 39,482 were error strings and other non-image files. The original goal was just to improve the http-favicon.nse script, but the nmap guys had enough fun browsing so many icons that they used them to create the visualization above.

The area of each icon is proportional to the sum of the reach of all sites using that icon. When both a bare domain name and its "www." counterpart used the same icon, only one of them was counted. The smallest icons--those corresponding to sites with approximately 0.0001% reach--are scaled to 16x16 pixels. The largest icon (Google) is 11,936 x 11,936 pixels, and the whole diagram is 37,440 x 37,440.