Facebook

Here’s what Facebook knows about you, and how to download all your data

Ben Lovejoy | Mar 12 2018 - 5:03 am PT

Facebook has long allowed you to download an archive of all the data the social network has on you, and HackerNoon’s Georges Abi-Heila decided to find out exactly what company knows about its users …

Abi-Heila reports (via TNW) that his archive was a 500MB zip file, and it included everything from the day he joined the service.

Quite simply, Facebook never deletes anything. Unfriended friends, past relationships, former employers, previous names, address book: you name it.

I created my account Friday, September 14, 2007, at 10:59 am and all my actions have been recorded ever since. I feel that for the first time in history, 10 years of consistent human behavior have been meticulously gathered, stored & analyzed.

Some of the data is more detailed than you might expect.

Whenever you post a photo to Facebook, it keeps a record of all the data that’s attached to it. That seems quite obvious but I didn’t suspect it was so detailed. Have a look: Camera Maker, Model, Orientation, Exposure, F-Stop, ISO Speed, Focal Length, Latitude, Longitude & Upload IP Address.

So Facebook knows where you were every time you took a photo uploaded to your wall, and session data tells it not just your location but also your IP address.

If you’re part of the 1.4B people that use Facebook on a daily basis, they have enough data points to determine your everyday life patterns with great accuracy: home and work address, daily commute, wake up & bedtime, travel duration & destination, etc.

And it can recognize you whether or not you are tagged in a photo.

Facebook allegedly said that its image recognition models could recognize human faces with 98% accuracy & that it could identify a person in one picture out of 800 million in less than five seconds.

If you allowed Facebook access to your address book, it keeps that contact data forever.

Abi-Heila found that very few advertisers had access to any of his personal data – just 21. This is less surprising that it might seem given that it happens only if you grant permission. But advertisers can use a wide variety of anonymous data to target you.

Facebook Business platform provides some details about what info is used in custom audiences targeting: city, state, country, date of birth, age & gender.

You can download a copy of your own data by clicking the chevron top-right, then Settings. In a fairly unobvious place beneath the settings is a link to the download: