Reverse tracking wall in two lines of JavaScript

Let's build a simple reverse tracking wall. This is a way to encourage users to install or configure tracking protection, by rewarding them with access to particular web pages.

Step zero. Make a page that we want to protect. Done. We were going to do that anyway.

Step one. Add the scripts to the page. First is the Aloodo script. This is the same script that does tracking tests and warnings.


In order to get a reverse tracking wall instead of just a warning, we just need to set the variable trackingAlternateLocation. This is where a user gets bounced to, if the script detects that the browser is vulnerable to tracking.

var trackingAlternateLocation =

That's it for step one. The next step, wait, there's only one step. All done.

Want to see it in action? Visit the new page protected by a reverse tracking wall. See what happens if you visit from a vulnerable browser.

This is a simple client-side reverse tracking wall, and users with a little web knowledge can get around it, just as users with web knowledge can evade web site paywalls. But users who know about web security are probably already using tracking protection anyway. Reverse tracking walls are for unprotected users, to help them justify spending the time to do a simple fix.

Data leakage is an ongoing problem that feeds fraud, malvertising, a race to the bottom in ad revenue, and a failure to build brands online. A reverse tracking wall is one way to give a site's users the incentive to help fix the data leak upstream, in the browser.

Don Marti · #