Tracker Radar includes the most common cross-site trackers, plus detailed info on things like their prevalence, ownership, cookie behavior and privacy policy. According to CNET, the data set contains details on 5,326 domains used by 1,727 companies to track users online. DuckDuckGo hopes that developers will use Tracker Radar to block online tracking and that researchers will use it to better understand tracking.

For everyone else, Tracker Radar is built into DuckDuckGo Privacy Browser mobile apps and the DuckDuckGo Privacy Essentials desktop browser extensions (available for Chrome, Firefox and Safari). All of those block the trackers on the Tracker Radar list.

Web trackers, which gather data on users location, search and browsing histories, are common, but companies are beginning to push back. Chrome now lets you block cross-site tracking, and Google plans to nix third-party cookies in Chrome by 2022. Firefox 69 blocks cookies and crypto-mining tracking by default, and Microsoft has tested protections in its Edge browser.