How Marketers Use Device Fingerprinting To Target You

What is Device Fingerprinting?

Device fingerprinting is a stealthy practice that involves collecting a unique set of data points from your device and browser, creating a distinctive "fingerprint" of your online presence.

Unlike cookies or IP addresses, device fingerprints are much more intricate and difficult to hide. A device fingerprint can be made up of multiple pieces of information, such as:

• User-Agent String
• Browser Plugins
• Screen Resolution
• Time Zone
• Language and Locale
• Installed Fonts
• System Fonts
• Browser Configuration
• IP Address
• Device Hardware
• Time Zone Offset
• Platform Information
• Battery Status
• WebRTC Information
• HTTP Accept Headers
• Canvas Fingerprinting
• Web Storage
• Audio Fingerprinting

All of these data points may appear pretty inconspicuous on their own but when combined, they create a remarkably precise profile.

Your digital fingerprint can be as unique as the print on your thumb and can be used to pick you out from the web full of users and track you as you move about online.

This makes it a very valuable tool for marketers and advertisers.

How Marketers Exploit Device Fingerprinting

Marketers used to rely on cookies to track users, but they started to come up against privacy regulations that made this difficult. It's now also easier for users to block and delete cookies. To combat this, marketers adopted a more invasive practice of device fingerprinting.

From the POV of an advertiser, device fingerprinting lets them understand their audience better. It gives them the ability to create individual user profiles, track users, and target them with highly personalized adverts.

For example, just by examining the user agent, advertisers can gain insights into your device. They can figure out if you're using a premium device like a Macbook Pro or a budget-friendly smartphone.

Combine that with details about your IP address, time zone, and language settings and a marketer can make an informed guess as to your exact location and your economic standing.

Marketers also use device fingerprinting in their analytics. They can identify and report on new and returning visitors. This enables them to analyze ad campaign outcomes and track their effectiveness and performance. They can make changes to their campaigns to make them more appealing to you.

What Are the Privacy Concerns?

Here are a few reasons why you should be concerned about how advertisers use device fingerprinting:

Invasive Tracking

Device fingerprinting allows marketers to follow your online activities closely. They can build a comprehensive picture of your preferences, habits, and interests without your knowledge. This might not be information that you want people to know. And you might not want to see adverts based on every part of your browser history.

Lack of Consent

Unlike cookies, which can be managed or blocked, device fingerprinting occurs behind the scenes. Most general internet users are completely unaware that their online activities are being monitored and shared with third parties.

Users are not informed about the use of device fingerprinting, and there is usually no clear way for them to opt-out or control the data collection.

Anonymity Erosion

Fingerprinting can often strip away online anonymity that users expect when they go online.

Cross-site tracking of device fingerprints allows marketers to link a user's activities across different websites, even if they use different usernames or accounts. This makes it difficult for users to maintain separate online personas and remain anonymous.

When combined with other information, device fingerprints can be used to de-anonymize users. For example, if an online service knows a user's device fingerprint and can link it to other personally identifiable information, it becomes much easier to identify and track the user.

When advertisers and marketers use device fingerprints to target users with personalized ads it not only erodes online anonymity but also invades users' privacy by showing them ads based on their interests and online behavior.

Protecting Your Privacy From Device Fingerprinting

When you search for protection from device fingerprinting, there are a few common solutions that are recommended. But not all of them are actually up for the task.

Let's take a look at each of the common anti-fingerprinting options and explore how effective they are:

Browser Extensions

Privacy-focused browser extensions like Privacy Badger, uBlock Origin, or CanvasBlocker are a popular choice in trying to prevent or limit the collection of device fingerprints.

But, most of these extensions will only work for a few data points. Also, it appears that fingerprinting by browser extensions is also possible (at least on Chrome).

The likelihood of two people having the exact same combination of browser extensions is around 0.006%. So, even though you might be installing an extension that is meant to block fingerprinting, you could simply be making yourself even easier to identify.

Regularly Clear Cookies and Cache

Clearing your cache and cookies can disrupt device fingerprinting by removing or altering some of the data points. However, it's not a foolproof solution.

Other fingerprinting techniques, such as browser fingerprinting, can still work just as effectively even if cookies and cache are cleared.

Use VPNs

Although VPNs are often cited as helping internet users improve online privacy and anonymity, this is a huge fallacy.

All VPNs do is mask your IP address.

Your IP address is only one piece of the puzzle. Device fingerprinting relies on a multitude of other data points, such as browser configurations, fonts, plugins, and more. Even if your IP address is hidden, these other factors can still be used to create a unique fingerprint.

Another factor to consider is that using a VPN or not, is also a fingerprint.

As the use of VPNs has become more widespread, it has also made it easier for advertisers to distinguish between users who use VPNs and those who don't. It's distinctions like this that can be used as an additional identifying factor.

Adjust Browser Settings

Tweaking your browser settings isn't going to stop device fingerprinting, but it can reduce its effectiveness.

Here are a few adjustments you can make:

• Disable Third-Party Cookies
• Block JavaScript
• Disable WebRTC
• Prevent Pop-ups and Redirects
• Switching to a privacy-focused search engine

Just be aware that disabling too many features or using extreme settings can negatively impact your browsing experience. For example, disabling or limiting JavaScript can significantly reduce the amount of data that can be collected about your device, it does also affect the functionality of many websites.

Browser Fingerprinting Test

Regularly check your browser's fingerprint using tools like Cover Your Tracks by the Electronic Frontier Foundation (EFF). This helps you understand how unique your configuration is and lets you make adjustments accordingly.

Download Hoody

The above anti-fingerprinting techniques can only do so much. Some are better than others while some are completely ineffective in combating device fingerprinting...(We're looking at you, VPN!).

Hoody, on the other hand, is a dedicated privacy app that is specifically designed for the task of stopping you being tracked by fingerprinting- device and browser.

Where the anti-fingerprinting methods fail is that they apply the same spoofed data for every website. The details may be fake, but the "same fake" data can still be correlated and tracked.

Hoody does it differently.

It spoofs fingerprints and IP addresses on EACH website. And, that info fed to the websites is based on real desktop fingerprints, not just garbage data.

It's only by using different IPs and fingerprints on each website that you can achieve true anonymity.

Stop Marketers in Their Tracks

Device fingerprinting is a powerful tool for marketers. But what helps the advertising industry poses a significant threat to our online privacy and personal data. Staying informed about these practices and taking the necessary measures to protect your online identity is essential to safeguard your online identity.

If you're wondering why online privacy is worth fighting for, then read more here: What Is Digital Privacy And Why Does It Matter?