How to . . . find out what Facebook knows about you

From personal data to web browsing habits, we reveal far more than we think online

A few years ago, the idea of handing over every detail of your personal life to a website would have been completely alien. But like it or not, that's what many people do when they sign up for Facebook. Every milestone is recorded, every family event is shared; even the places we go are tagged and tracked.

Perhaps you are a bit more careful about what you share, but even being cautious, we often give away a bit more than we think when we use social networks every day.

Here’s how to find out exactly what Facebook knows about you, and how you can manage that information.

Your personal information:

When you sign up for Facebook account, you would have given it a certain amount of information, such as your name, date of birth and an email address to associate with the account. But over time, you’ve probably added to that. You may have added a relationship status, or given the site your mobile phone number as an added security measure should you ever get locked out of your account. Connections you have made over the years are all logged too, as are check ins.


Most of that information is viewable in your personal profile, or through your activity log, including the date you made changes to such information.

But there is other information that’s not as readily available. For example, you can find out what ads you clicked on and what IP addresses have been used to log in to your account.

To get a copy of this, click on the arrow in the top right corner of the desktop site. Then select Settings, and you’ll see an option at the bottom of the screen to download a copy of all your Facebook data. That archive includes everything you’ve ever posted on Facebook, including wall posts, photographs and private messages. Select Download a copy of your Facebook data, then select Start my archive. It will download as a zip file to your computer, and you can see your activity on the site in one very long, somewhat cringe-inducing trip down memory lane.

Your contacts:

At some point when you logged into your Facebook mobile app or, more recently, Messenger, you may have been prompted to sync your phone contacts with Facebook. That means a copy of your smartphone contacts has been uploaded to Facebook’s servers and associated with your account. No one else on your Facebook account can see the information but you; however, you may be regretting handing it over.

The good news is there’s something you can do.

Click on the arrow in the top right corner of the desktop site. Then select Settings, and you'll go to Facebook's page for managing invites and contacts here. You'll see an option to delete selected contacts, by checking the box next to each one, or to remove all imported contacts in one go. Choose whichever option suits your needs, and confirm it. You can also see what contacts have been uploaded through Messenger by clicking here and removing them if you so wish.

Some contacts may remain because they aren’t imported from your phone book, but rather that your friends have chosen to share their mobile numbers with you on Facebook.

Finally, make sure you’ve disabled autosync for your contacts in Messenger else you’ll find your address book is back on your profile before long. In Android, tap the cog in the corner of the screen, then tap People >Synced Contacts, and switch off the setting. In iOS, tap the cog icon, and tap Synced Contacts to disable the autosync.


Facebook is in the business of selling ads, and like it or not, if you’re a Facebook user, you’re the target of them. The social network uses your activity on the site to build a nice profile of you with the intention of using it to better target ads. So when you change your relationship status to engaged, you suddenly find that your Facebook profile includes ads for wedding venues; when you cross a milestone age, the ads also change accordingly. Express an interest in a particular topic by liking a page on Facebook, and that will be filed away for future use too.

Completely opting out of ads isn’t possible, although using an ad blocker will decrease the number you see on the desktop site, but you can influence what you see to a certain degree. Facebook has an ad preferences page that allows you to remove certain information that could be leading to you being served ads on particular topics. To access it, find an ad, and click on the arrow in the right hand corner of it. That will drop down a menu, with the option Why am I seeing this? Select that, then click on Manage your advert preferences. You can then delete the information and topics you feel aren’t relevant to you.

What about what goes on outside Facebook? The social network can also gather some of your web browsing habits on sites that use Facebook’s technology, but you can put a stop to that. Click on the lock icon in the top right corner of your Facebook page, then select See more settings>Adverts. On Adverts based on my use of websites and apps, choose edit, and turn it off. You can also choose to stop Facebook ad preferences being used to show you ads on apps and websites distributed using the Facebook audience network, and prevent your social interactions being used with ads.

Again, none of this will cut down the number of ads or sponsored posts you see on Facebook – it just makes it a bit less creepy and tailored to your web browsing habits.