You ‘fingerprint’ is the set of seemingly innocuous data that your browser and your system expose every website you visit. We are not talking about your name or your ID, but about more technical aspects: operating system and version, browser and version number, time zone, system language, keyboard layout, screen resolution, list of fonts, available extensions and APIs, graphic rendering parameters (WebGL, canvas), among others. Each one, separately, does not identify you. But Combined, they are usually unique enough to distinguish you among millions of users.
That uniqueness can be verified with online tools such as AmIUnique either Cover Your Trackswhich show how much of that information your browser filters out and how likely it is that your combination is unique. Even with popular configurations (Windows + Chrome), the result can be unique; and with very specific details – such as the WebGL profile – the uniqueness increases, they explain from Wired.
This technique, called browser fingerprinting, It is probabilistic. That is, it does not assign an unambiguous identifier like a cookie, but it creates a very reliable one based on your technical pattern. It is used for cookieless advertising and analytics, fraud prevention (smart blocking of suspicious logins or payments), account sharing control and, to a lesser extent, malicious purposes against high-profile targets. Legally, its loose components are not personal data, but aggregation for identification purposes falls under the scope of the GDPR and if a company manages that profile to identify you, it needs a legal basis and, in general, your consent.
There are studies that place the effectiveness of browser fingerprinting from the 35% even above the 95%; Accuracy varies depending on the device and your browsing habits. In practice, even if you use a VPN, if the rest of your settings remain stable, it is possible to correlate your visits between different sites, browsers, and even sessions.
What you can do to avoid browser fingerprinting
There is no way to delete it without sacrificing functionality and comfort. The realistic goal is ‘dissolve yourself in the crowd’; that is, reducing the uniqueness of your profile and rotating attributes to make it more difficult to track. To achieve this, you can take these measures:
Hide the obvious (IP and location)
A VPN Reliably reduces your footprint by hiding your IP and physical location. If it includes blocking trackers at the level DNS/HTTP (tracking and malvertising lists), better, since it limits the third parties that receive your signals.
Use browsers with native defenses
There is two main options that offer you greater security by default and without having to complicate yourself with configurations:
- brave randomizes and standardizes responses to sensitive APIs (canvas, WebGL, AudioContext), blocks third parties, and reduces uniqueness so that Brave instances resemble each other.
- Firefox offers Enhanced Tracking Protection and, with the Multi-Account Containers plugin, isolates sessions by ‘containers’ (social media, shopping, news), preventing cross-contamination of identifiers. Also activate site isolation and block third-party cookies.
Deviates or normalizes high-value attributes
Extensions like those from some VPN/privacy providers allow you to rotate the ‘user agent’ (the identification string that your browser sends in each web request) and synchronize language, time zone and GPS with the chosen server. It’s best to use it sparingly, as aggressive spoofing can make you more unique if your combination doesn’t match the rest of your environment (e.g. system language vs. time zone).
Reduce the details that make you different
Keep your browser updated, uninstall unnecessary fonts and extensions, avoid exotic themes and settings, and use default settings when possible. The more standard, the less identifiable you are.
Control status between sessions
Clean site data regularly, disable automatic login where it is not essential, and separate identities with browser profiles/users. Don’t just rely on ‘clear cookies’fingerprinting persists without them.
For extreme privacy needs
The browser Thor (with its network) standardizes parameters and routes traffic through multiple nodes. It’s slow and many sites block it, but it provides the most consistent pattern.
Disable JavaScriptsomething that all browsers allow from their options, cuts off most fingerprinting techniques. The problem is that it can cause many aspects of a website to not work and this is something you will encounter frequently, given that the vast majority of websites use JavaScript.
In short, it combines VPN + browser with anti-fingerprint protections + extension and profile hygiene. You will not be able to be invisible on the internet, but you will be less unique and more similar to the group.