If you’ve spent the past week binging on the latest series of Black Mirror, you might be feeling a little edgy about technology. While your existential anxiety about cyberspace can wait a little while, it’s totally understandable that you might be concerned about your privacy on the Internet.

Fortunately, there’s a simple tool made by Supremo that can tell you how much of the stuff you put on Facebook is accessible to strangers.

Every time you share something on Facebook, you are given a range of privacy setting options for that post. It's very simple to change the settings, but if you're unaware of the options then your personal information could be available for everyone to see, from annoying advertisers to criminals.

Start by heading over to the website here and allowing it to access Facebook. It seems a little ironic permitting the tool to access your personal information, however, they do say that "information we've gathered will be completely removed from our records but there are more malicious uses of your personal information potentially."

The tool will ask you rather creepy questions, such as: “How was your visit to the Natural History Museum in London 46 days ago?” It will also show you a random photograph of yourself and other personal information, such as the school you went to, your workplace, your partner's name, your family members, your email address, and the events you've attended. Creepy.

“The point is simple! We all need to be very careful about how we choose to spare our information online and who with,” Supremo explain. “After you close this window all of the information we've gathered will be completely removed from our records."

Supremo has also created a series of “cheat sheets” and guidelines on what and when to share online. There’s the obvious things, like your credit card details, but also some tips you might not necessarily have thought about, such as being too explicit that you're away on holiday (thereby telling thieves your house is probably empty at that moment).

The moral of the story, Supremo argues, is to remain cautious.