Browser fingerprinting is a way to track you online. It uses data from your device. Sites collect details like screen size, fonts, and plugins. They build a unique“fingerprint.”This fingerprint can follow you across sites. Companies use fingerprinting to guard data. Banks check fingerprints to stop fraud. Advertisers use them for better ads. Yet, users worry about personal privacy. In this case CreepJS helps balance both sides. It raises awareness and guides safer designs.
CreepJS is a free, open-source tool for browser fingerprinting tests. It runs small JavaScript scripts in your browser. Then it gathers many data points. It checks your user agent string to know your browser and version. It reads canvas and WebGL data to see how your device draws images. It logs installed fonts and screen size, which vary from one user to another. It even notes time zone, audio context, and device memory, giving extra clues about your machine.
CreepJS also inspects HTTP headers. It sees which languages your browser accepts and whether you use cookies or do-not-track settings. It tests WebRTC to reveal local IP addresses. All these details form a unique profile. Sites call this profile your “fingerprint.”
With CreepJS, developers see exactly what data sites can use. For example, CreepJS might draw a hidden image on your canvas and then read back pixel data. That pixel map is often unique to your device’s graphics card and driver. Your screen resolution, installed fonts, plugin list, and even battery status add more uniqueness. CreepJS logs each value and shows which ones repeat across tests.
By running CreepJS on different machines or profiles, teams can compare results side by side. They can rank which data points are most stable and which vary often. This helps them decide what to mask or randomize. In short, CreepJS gives a clear window into browser fingerprinting. It points out exactly where privacy leaks might occur—and where engineers need to focus.
When you run CreepJS in your browser, it taps into several core web APIs. First, it uses the Console API to log results. The console is a built-in browser tool that shows messages and data structures. CreepJS prints a JSON object there. JSON (JavaScript Object Notation) is a simple text format. It makes data easy to read and parse. You can copy this JSON and save it to a file.
CreepJS will calculates a stability score for each data point. This score shows how reliable a value is across runs. For example, your screen resolution rarely changes. So that score is high. But fonts can change if you install new ones, so that score is lower. By ranking these scores, you see which values matter most. Then you know where to focus your masking or randomization efforts.
Under the hood, CreepJS uses the Canvas API and WebGL to fingerprint graphics. The Canvas API draws 2D shapes and text. CreepJS draws hidden shapes and reads back the pixel data. This pixel map is a unique “canvas hash.” WebGL taps into your GPU for 3D rendering. CreepJS asks WebGL for vendor and renderer strings. Together, canvas and WebGL give a powerful fingerprint.
To harden your site, you can override these APIs. In DICloak or custom code, you stub out the HTMLCanvasElement.prototype.getContext method. Then you return random pixel data instead of the real data. You can also block WebGL calls entirely.
After you apply these fixes in your code or DICloak profile, simply rerun CreepJS. The console or log file should now show varied canvas hashes, fake user agents, and other shifted values. This clear before-and-after view proves your countermeasures work.
Using CreepJS in this way helps you meet compliance requirements like GDPR and CCPA. These laws require you to minimize data collection and protect user privacy. By testing with CreepJS, you can certify that your site only collects what is strictly needed. In turn, you build user trust, reduce legal risk, and stay ahead of evolving web threats. CreepJS thus serves as both a diagnostic tool and a guide for best practices in browser fingerprinting defense.
You can use CreepJS alongside an anti-detect browser to test real-world defenses. First, run CreepJS in a normal browser. Note which data points leak. Then switch to DICloak, a powerful anti-detect browser. DICloak masks or randomizes those same points.
When you launch CreepJS inside DICloak, you’ll see a different result. Your canvas data changes. Your user agent string shifts. Plugins and fonts hide behind safe defaults. Time zone and audio context no longer match your real device. This shows that DICloak stops CreepJS from building a stable fingerprint.
This pairing brings two main benefits. One, it proves your anti-detect setup works. You get clear, side-by-side logs of before and after. Two, it helps you fine-tune settings. If CreepJS still finds one data point, you can adjust DICloak’s rules until it disappears.
For example, a marketing team might test how often CreepJS spots a repeat user. They run ten tests in a default browser. All ten share the same fingerprint. Then they run ten tests in DICloak. Each one looks unique. This reduces tracking and ad retargeting risks.
By combining CreepJS with DICloak, you meet both privacy and compliance goals. You prove your site can’t track real visitors by fingerprint. And you ensure tools like CreepJS can’t expose your users. This builds trust and keeps you ahead of evolving web threats.
4. Run CreepJS Inside DICloakIn DICloak’s browser window, load the same HTML test page.Open the console again to view the new fingerprint.Compare these values to your baseline. You should see changes in canvas data, fonts, and time zone.
5. Analyze and TuneIf CreepJS still picks up a constant value, return to DICloak’s settings.Adjust the randomization level or add custom masks.Repeat the test until all key data points vary each run.
6. By following this clear workflow, you validate that DICloak blocks CreepJS from creating a stable fingerprint. This process meets privacy and compliance needs. It also builds real-world confidence in your anti-detect setup.
Q1. Is browser fingerprinting illegal?
A: Browser fingerprinting itself is not illegal. It is a tracking method. Laws like GDPR and CCPA limit how you use the data. You must get consent if you store or share fingerprints. Tools like CreepJS can help you test compliance.
Q2. What is the use of FingerprintJS?
A: FingerprintJS is a popular JS library for fingerprinting. It collects data points to build a device profile. Many sites use it to detect fraud and bots. You can compare it with CreepJS to see what each tool reveals.
Q3. Is browser fingerprinting good or bad?
A: Browser fingerprinting can be both. It helps fight fraud and improve security. But it can also harm user privacy. Using CreepJS shows you exactly how much data a site can collect. Then you can choose to protect or limit fingerprinting.
Q4. What is the best browser fingerprint library?
A: There is no one “best” library. FingerprintJS is feature-rich. CreepJS is simple and free for testing. Other options include AmIUnique and ClientJS. You should pick the tool that fits your needs and compliance goals.
Q5. Can hackers steal my fingerprint?
A: Hackers can read your fingerprint if they run scripts on your browser. They may use it for tracking or to bypass security checks. By testing with CreepJS and masking with an anti-detect browser, you can see and block these attempts.