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

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.