How to track your Facebook friends’ sleeping habits

David Bisson

How to track your Facebook friends' sleeping habits


A privacy advocate has developed a tool that enables you to track the sleeping habits of your friends on Facebook.

Søren Louv-Jansen, a developer at Tradeshift, explains that he was first motivated to develop the tool, which is available on his Github page, when his girlfriend complained that her friends knew whenever she logged onto Facebook’s website, its mobile app, its Messenger app, or its web-based version

This is not the first time the amount of personal information Facebook collects has piqued someone’s creativity.

In May of last year, news first broke about a Google Chrome browser extension known as “Marauder’s Map” that scrapes information from your Facebook Messenger page and plots it on a map. Creepy stuff, to be sure!

Well, it just got creepier.

After digging around a feature of that allows you to see when a user was last active, Louv-Jansen happened upon a list of user IDs and timestamps of when they were last active.


This gave Louv-Jansen an idea, as he describes in a blog post:

“By creating a simple service that checks Facebook every 10 minutes, I’m able to get an accurate picture of my friends’ Facebook usage. Many people visit Facebook as the first thing in the morning, and the last thing before going to bed. It is therefore possible to get a good impression of their sleeping habits (or lack thereof).”

The developer ultimately determined that his service worked accurately for 30 percent of his friends for Monday through Friday, when sleeping patterns are more regular than on the weekends. His tool worked somewhat for the remaining 70 percent of his friends.

Sleep chart
Apparently, Facebook hasn’t taken too kindly to Louv-Jansen’s efforts.

The Washington Post reports that Facebook contacted Louv-Jansen, saying that as the service violates its terms and conditions, he should not encourage anyone to use it.

The developer has since stopped using his service, but for the sake of public education, he has refused to take it down from GitHub:

“I’m not proud of people starting to spy on their friends. But maybe this can make everybody more aware of the consequences of our actions.”

Everything we do online leaves a digital footprint, and Louv-Jansen’s service only proves that point

Some may abuse the privacy advocate’s tool for their own misguided and nefarious purposes. But we can hope that a larger section of users will be inspired by the tool’s implications to review the content of their digital lives. Perhaps they’ll look into using a VPN or disabling cookies whenever they search the web. Maybe they’ll even try to shake up the times when they log in to Facebook.

It’s ultimately up to the user, but what is important is that they know what’s going on – and what information is being collected about them – so that they can make an informed choice.

If you are on Facebook, and want to be kept updated with news about security and privacy risks, and tips on how to protect yourself online, join the Graham Cluley Security News Facebook page.

flickr photo shared by Aleera* under a Creative Commons ( BY-ND ) license.

David Bisson David Bisson is an infosec news junkie and security journalist. He works as Contributing Editor for Graham Cluley Security News and Associate Editor for Tripwire's "The State of Security" blog.

2 Replies to “How to track your Facebook friends’ sleeping habits”

  1. 'Privacy advocate releases tool that may give people nightmares about their use of social networks'

    Or perhaps not… it seems no matter what happens with social media so many people ignore it – if they're even aware of it. Of course some might find it alarming (and clearly that is the case) but it certainly isn't surprising (at least not to me). What might be more alarming is that so many people don't react to these things (if they even see it and if they don't that isn't so alarming but it is unfortunate). I think the other part: 'may'. Unfortunately not 'will' or remove it all together and tack an s on the give ('that gives people').

    'In May of last year, news first broke about a Google Chrome browser extension known as "Marauder's Map" that scrapes information from your Facebook Messenger page and plots it on a map. Creepy stuff, to be sure!'

    When I saw the title of this post I had the same recollection almost immediately. The name was perfect, though, regardless of the implications [of it].

  2. The comical thing about this app is that Facebook and other companies have been blatantly invading your privacy for decades now. Only when someone else does it do they seem to mind.

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