Here’s how to see all the really creepy stuff Facebook knows about you

When it comes to privacy, Facebook really isn’t your friend - and even if you’re careful, you might be giving away more than you think.

Facebook builds up a hidden dossier of data on every user - a frighteningly detailed picture of that person, built from how they use Facebook and other sites.

News organisation Pro Publica has created a Chrome plug-in which reveals exactly what Facebook knows, in an easy-to-read format.

For instance, Facebook usually knows your marital status, whether you have children, what phone you use - and other highly personal data you may not have chosen to share with the site.

To use Pro Publica’s plug-in, simply install it from here, and then click the icon to see what Facebook knows.

You will need to be using Chrome, obviously, and be logged in to Facebook.

Pro Publica says, ‘When [users] browse the Web, Facebook collects information about pages they visit that contain Facebook sharing buttons. When they use Instagram or WhatsApp on their phone, which are both owned by Facebook, they contribute more data to Facebook’s dossier.

‘And in case that wasn’t enough, Facebook also buys data about its users’ mortgages, car ownership and shopping habits from some of the biggest commercial data brokers.’