Ghostery Browser Plugin Reveals Every Company That Tracks You

True privacy online is hard to come by, especially because once you entrust a company with your data, the whole Internet usually learns a thing or two about you.

Ghostery is an Internet browser plug-in that determines which companies are tracking you on every website you visit — and lets you do something about them. Tom's Guide stopped by Ghostery's booth at SXSW 2014 to learn more about how the program works.

Companies track users online more often than they think. A single site may have ads from a dozen different providers, as well as social media widgets that retain login information and separate video providers that embed themselves into a website.

MORE: 13 Security and Privacy Tips for the Truly Paranoid

Being tracked is not necessarily a bad thing; after all, it's convenient for a site to let you log in via your Facebook account, or to watch a video from YouTube right in the middle of a news story. Still, Ghostery wanted to provide users with a way to see just how many eyes are on them, and to give them the option to do something about it.

Users can download Ghostery for free from its website and install it for any major browser. After that, clicking on the plugin's icon will bring up a list of trackers on each site. Companies that track users often provide nothing more than harmless analytics or widgets, but Ghostery can also pinpoint and disable intrusive or potentially dangerous ads.

After bringing up Ghostery's list of trackers, users can then enable or disable each one individually, and can pause blocking temporarily or choose to whitelist an entire site. Clicking on a tracker's name will also reveal more information about the company behind it, including whether or not the tracker poses any danger.

Although Ghostery is free, it does not require user donations to keep running. Rather, many major companies have lost track of exactly how many trackers operate through their websites, and pay Ghostery to put together reports. Simply by using Ghostery and opting to share your information, you are already paying your dues to the program.

If you want to be granular with your Internet privacy rather than just blocking every ad outright, Ghostery provides a simple, comprehensive tool to do so. Just try not to be shocked when you see how many advertisers track you via your favorite sites.

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Marshall Honorof

Marshall Honorof is a senior editor for Tom's Guide, overseeing the site's coverage of gaming hardware and software. He comes from a science writing background, having studied paleomammalogy, biological anthropology, and the history of science and technology. After hours, you can find him practicing taekwondo or doing deep dives on classic sci-fi.