How websites can track and identify your browser as unique?

When you clear browsing history, delete the cookies and clear the cache you expect your browser to be not trackable. If you think about individuals certain singular information is not all that important but a combination of them can allow you to differentiate if not identify the individuals.

If you know the Zipcode of ten people there is no way to distinguish one from the other if two or more have the same zip code. But if you know a combination of zipcode, gender and date of birth then the person would be very uniquely identifiable and hence trackable.

In terms of browsers this information is often stored by servers when you visit a website for tracking statistics. Most analytical services track individual visits, unique visitors on websites with a combination of some information which makes the individual visitor unique and hence trackable.

About Panopticlick

  • Ideally we think if we clear browsing data and use incognito mode for making use our stats are not tracked by a tracking service.
  • That is not true. Despite all this your browser and its visits can be recognised as unique and tracked by a service.
  • Visit Panopticlick after you have cleared all browsing data. Let it look up the uniqueness of your browser.

For instance I used my Chrome browser with all details removed and logged into Panopticlick with in incognito mode. Here it identified browser characteristics as User Agent, Browser plugin details, Time Zone, Size color and details. As I mentioned before none of these characteristics can give a unique identity about the browser. But a combination of all these create a unique identity for a website to track individual browser. 😉

Link: Panopticlick