Every time you browse the web, you're being tracked. Most websites contain invisible tracking code that allows companies to collect and monetize data about your online activity. Many of those companies are data brokers, who sell your sensitive information to anyone willing to pay.

How does Privacy Badger work?

When you view a webpage, that page will often be made up of content from many different sources. For example, a news webpage might load the actual article from the news company, ads from an ad company, and the comments section from a different company that’s been contracted out to provide that service.

Privacy Badger keeps track of all of this. If the same source seems to be tracking across different websites, then Privacy Badger springs into action, telling the browser not to load any more content from that source. And when your browser stops loading content from a source, that source can no longer track you. Voila!

At a more technical level, Privacy Badger keeps track of the “third party” domains that embed images, scripts and advertising in the pages you visit. Privacy Badger looks for tracking techniques like uniquely identifying cookies, local storage “supercookies,” and canvas fingerprinting. If it observes the same third-party host tracking on three separate sites, Privacy Badger will automatically disallow content from that third-party tracker.

By default, Privacy Badger receives periodic learning updates from Badger Sett, our Badger training project. This “remote learning” automatically discovers trackers present on thousands of the most popular sites on the Web.

What is a third party tracker?

When you visit a webpage parts of the page may come from domains and servers other than the one you asked to visit. This is an essential feature of hypertext. On the modern Web, embedded images and code often use cookies and other methods to track your browsing habits — often to display advertisements. The domains that do this are called “third party trackers”, and you can read more about how they work here.

What do the red, yellow and green sliders in the Privacy Badger menu mean?

Red means that content from this third party domain has been completely disallowed.

Yellow means that the third party domain appears to be trying to track you, but it is on Privacy Badger’s cookie-blocking “yellowlist” of third party domains that, when analyzed, seemed to be necessary for Web functionality. In that case, Privacy Badger will load content from the domain but will try to screen out third party cookies and referrers from it.

Green means “no action”; Privacy Badger will leave the domain alone.