Browser Fingerprinting: What Is It and How Can I Protect Myself?

Martin Gschwentner

You're not like everybody else. You're unique. What sounds like a harmless and a bit cliché motivational saying can have some dark and serious undertones when you're talking about data protection and privacy on the internet. Because the uniqueness of your identity makes you vulnerable – to advertising, data trade and misappropriation.

What Is a Browser Fingerprint?

You might think you're surfing the Web anonymously, but every click you make with your device leaves traces of information about yourself behind.

Whenever you're online, your device provides the websites you're visiting with specific data. This can be information about your operating system or your settings. The site might even know what hardware you're using.

The act of someone trying to use that data in order to identify you is called 'browser fingerprinting'. Websites do this, for example, in order to detect what browser and plugins you're using, what language you speak, what resolution your screen's in, even what timezone you're in, and many other things.

This is how they identify unique visitors and track their online activity.

Browser Fingerprinting: Good or Bad?

Your data is exactly what international marketing services are looking for. Based on that information, websites display ads that are relevant to you in order to entice you to buy stuff. Data thieves and malware attackers use that information as well.

However, there are good reasons why platforms collect your data. Banks, for example, can use your online fingerprint to prevent fraud.

Browser fingerprinting in itself isn't bad – it still gives one enough reasons to worry.

How Accurate Is Fingerprinting?

There's a reason why the term includes the word 'fingerprint': As soon as a digital fingerprint is created, your identity can be ascertained. According to Mozilla, the method is "capable of identifying users correctly in 99% of cases."

Even if you block cookies, use a VPN, or follow any other kind of protective measures that are recommended for surfing the Web, your digital fingerprint can give you away.

How Can I Find out What My Personal Browser Fingerprint Is?

You can find out how unique your digital fingerprint is on websites like Panopticlick and Am I Unique. Test your browser and find out whether you can be identified easily – and need to act. offers a tool as well: Our Browser Privacy Check tells you what kind of traces you leave behind when surfing.

Why Should I Protect My Browser Fingerprint?

Whenever personal data is collected, there's a risk of misuse. Unlike other means of identification such as your IP address, your digital fingerprint is invisible and therefore more difficult to protect. Many users don't even know they're passing on their data.

Companies might sell that information to third parties to make a profit. At the same time, malware attacks can be carried out more effectively when personal data is involved.

How Can I Protect Myself From Browser Fingerprinting?

The bad news: It's almost impossible to entirely protect yourself from fingerprinting. The good news: You can still mitigate the degree of fingerprinting that's being done with the help of a few simple methods.


Use Your Browser in Incognito Mode

Surfing in Incognito Mode is the simplest method to reduce the size of your fingerprint. Almost every browser has this feature.

When you're surfing while in private mode, your browser doesn't save your browsing history. Your browser profile is set to a certain standard which is the same for every user surfing in Incognito Mode. That's why those users' digital fingerprints look very similar – the uniqueness of their profiles is therefore reduced.

This method isn't very effective because there's a plethora of other data that play into browser fingerprinting that surfing while in Incognito Mode has no impact on.


Use Tor Browser

If you're serious about this, you shouldn't just switch browser mode, you should switch browser. The Tor browser is set up in a way that every user's fingerprint is identical to that of others. In addition, the browser blocks JavaScript very effectively.

Depending on what features you've activated in your Tor browser, your identity is still only hidden to a certain degree. Plus, using a Tor browser isn't easy for almost anybody.


Deactivate JavaScript

Websites use JavaScript to detect plugins and collect information. This can define the profile of your digital fingerprint more narrowly. You can manually deactivate JavaScript in your browser or use tools like NoScript or AdBlock Plus.

Due to the fact that may website rely on JavaScript, deactivating it can severely impair your browsing experience.


Mask Your IP Address With a VPN

A VPN (Virtual Private Network) lets you access a secure and self-contained network through a protected tunnel and hide your IP. In this article, we explain how exactly that works and which providers you can choose from.

A VPN acts as an intermediary for your data, so web servers don't come into direct contact with your IP address.

Your IP address is only one aspect of your identity, and a VPN doesn't mask your browser's settings. A VPN alone doesn't offer much protection and is only effective in combination with other measures such as deactivating JavaScript.


Use Special Privacy Software and Extensions

Privacy and data protection are of constant concern to software developers, and many of them promise effective applications and extensions. Privacy Badger, for instance, blocks certain domains that use fingerprinting technology. Disconnect works similarly. In combination with a powerful ad blocker, these extensions should protect your online identity from harmful domains.

Browser Fingerprinting: There Is No Such Thing as Perfect Protection

As you can see, there's no waterproof way of protecting yourself from browser fingerprinting. Each of the measure we talked about have advantages and disadvantages.

To protect yourself at least a little bit better, you can combine different methods, but doing that might be too laborious for regular internet users.

You should still try to keep your digital fingerprint as small as possible. Software that everybody should use – like ad blockers or anti-malware – can help quite a bit.

Take the measures that make the most sense to you – and use Panopticlick or Am I Unique to make a before-and-after comparison to see if you successfully reduced your browser fingerprint.

Author (German Version): Martin Gschwentner
Martin Gschwentner majored in American Studies and Media Studies in Germany, the USA and France and works as a freelance editor in Paris. He is a doctoral student at the Institute for English and American Studies at the University of Paris Diderot, where he is researching the influence of money on US politics. On he writes about IT security, data protection and software for the self-employed and small businesses.
English Translator & Editor: Brendan Philipp
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