The “Off-Facebook Activity” tool lets you see — and somewhat control — what other sites and apps tell Facebook about you

Facebook users just got a new glimpse into and a little control over the myriad ways the social network tracks what they do when theyre not using Facebook. If you didnt already realize it, by the way, Facebook is tracking an astounding amount of what you do when youre not using the platform, an activity also known as living life in the real world.
The new Off-Facebook Activity tool, which the company announced last August, finally launched on Tuesday. It can tell you which companies are supplying Facebook with information about your real-world activity for example, that you visited their website or purchased a product from it.
Why does Facebook want this? Because it can then match that information with your Facebook profile and target ads to you (or, in Facebooks words, personalize your experience). A lot of times when you think Facebook is listening to your phone conversations based on how specific its ads are, its actually because of how extensive (and hidden) its offsite data collection is.
This in-depth tracking is why you might see, oh, I dont know, an ad for a play starring the venerable Kate Mulgrew immediately after a Star Trek: Voyager Netflix binge, even if you werent on Facebook at the time. This is also what allows many websites, including Facebook, to give you free services. So you are getting something out of this deal you just might not have realized you were making the deal in the first place, or how much data you were handing over. (The play was great, by the way.)
Accessing the Off-Facebook Activity tool to see how much Facebook knows about your life outside of Facebook is not exactly straightforward. You can go directly to the tool by clicking here. If youre trying to find it from your News Feed, youll need to go to Settings and then click Your Facebook Information. You should see a line for Off-Facebook Activity, and then just go to view. Then prepare to be flabbergasted. One of our reporters, for example, found that 518 apps and websites had shared her data with Facebook in some way:
Many of the sites on her list were ones she had just visited. Thats because a lot of sites use Facebooks trackers, which automatically collect and send visitor data back to Facebook. Even users with tracker-blocking extensions on their browsers will likely find dozens of instances where companies are sending personal data to Facebook.
The feature also allows you to opt out of some of this collection to a point. Clicking on a particular companys listing will bring up a dialogue that will give you a slightly more specific look at what data was collected. Theres also the option to Turn off future activity from that company. If youre looking for a nuclear option, you can click Manage Future Activity and then flip the blue switch on the right side of the page.
This seems like it would turn off all real-world data collection, but thats not exactly true. Right after you flip the switch, youll see a dialogue that says, Well still receive activity from the businesses and organizations your visit. This information just wont be associated with your account.
You can also delete your off-Facebook activity history by clicking Clear History on the activity list. A window will then pop up asking you to click Clear History again:
As the prompt says, youll still see ads but they wont be those creepy ads of a product you were just looking at on a different site.
If you dont like the idea of your Facebook behavior being tracked and used for ads, you might also (if you havent already) want to change your ad settings on Facebook (available in the Ads section of your Facebook settings). Turn off Ads based on data from partners, Ads based on your activity on Facebook Company Products that you see elsewhere, and Ads that include your social actions. Again, this wont completely shut off the tracking, but it will minimize it.
If you don’t like the idea of being tracked by Facebook at all, tough luck. Even if you delete all of your accounts for Facebook-owned service, including Instagram and WhatsApp, it feels like theres nowhere online or on earth that the social network cant access. At least Facebook is giving you some control over it.
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