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Your browser is leaking secrets—even when you're in incognito mode. Ever wondered how websites still know who you are? Meet CreepJS.
CreepJS is an open-source project. It shows how websites use browser fingerprinting to identify users. It looks at things like your device type, language settings, and how your system renders graphics. These small details form a unique pattern—just like a fingerprint. That’s why it’s called a creepjs fingerprint.
Most people don’t even realize this is happening. But if that sounds a little creepy to you, you're not alone.
In the past, websites tracked users with cookies. But today, many people block cookies or use private browsers. So websites turned to a new method: browser fingerprinting.
Browser fingerprinting works silently. It collects hidden details from your browser and device—like your fonts, screen resolution, and how your system draws images. This data forms a digital ID. Unlike cookies, you can’t delete it. You can’t turn it off.
That’s why CreepJS is important. It shows developers and researchers what websites can really detect.
Websites don’t need permission. But now—you finally have visibility.
They track. You inspect.
Why do websites do this? Some use fingerprinting to stop fraud or protect accounts. Others use it to serve better ads. But not all use is fair. Some websites track people in secret. That makes many users uncomfortable.
Is it legal? It depends on where you live. In the U.S., laws like the CCPA require companies to be clear about data collection. In the EU, GDPR says users must give consent. But fingerprinting often happens in the background—and that worries privacy experts.
So why not block it? It’s not that easy. Cookies are files you can remove. Fingerprints are built into your browser’s features. You can’t just disable them. That makes fingerprinting harder to detect—and harder to stop.
Still, it’s not all bad. Fingerprinting can help prevent fraud and stop cyberattacks. But it can also be used for tracking, targeted ads, or even surveillance.
So, is browser fingerprinting good or bad?
It depends on who’s using it—and why.
That’s where CreepJS steps in. It reveals the invisible—and helps you understand what your browser is saying about you.
CreepJS goes far beyond simply revealing what your browser is exposing — it deconstructs the entire fingerprinting process into clear, actionable insights. Rather than just showing raw data, CreepJS analyzes and validates how each browser attribute contributes to your unique fingerprint.
Here’s what CreepJS checks in detail:
Modern fingerprinting scripts utilize HTML5 Canvas and WebGL APIs to render complex images and detect hardware-level differences. These include GPU type, driver variations, anti-aliasing behavior, and shader support — all of which can generate a consistent "canvas hash" unique to your machine.
📸 Visual Example:
This fingerprint is extremely difficult to spoof and often used for persistent cross-site tracking.
CreepJS simulates how your browser processes audio signals using the Web Audio API. It evaluates:
📷Visual Example：
Even slight discrepancies in audio handling across devices and browsers can reveal your identity.
Browser locale settings — like time zone, language, currency format, and installed fonts — seem harmless, but together they form a powerful fingerprint. CreepJS captures:
📸 Visual Example:
These settings often reflect a user's region, device OS, or even specific software builds.
CreepJS analyzes low-level hardware and rendering details such as:
📷Visual Example：These subtle but stable attributes offer a high-entropy fingerprint and are difficult to fake consistently.
WebGL not only exposes rendering capabilities but also reveals your GPU vendor and backend renderer, like ANGLE or native Direct3D/OpenGL. CreepJS evaluates shader precision, parameter behavior, and supported extensions.
📷Visual Example：
If your GPU info doesn't match your user agent or platform, CreepJS will flag the inconsistency.
Through properties like navigator.userAgent, userAgentData, and platform, CreepJS uncovers:
📷Visual Example：
This allows CreepJS to assess the reliability of browser spoofing attempts.
CreepJS then provides a uniqueness score or match level, indicating how likely it is that your browser can be re-identified across sessions. The more unique your fingerprint, the easier it becomes for websites to track you — even without cookies or login data.
This level of granularity helps you see exactly where your privacy defenses succeed or fail, making CreepJS an essential tool for testing and improving anti-fingerprinting strategies.
So, how does CreepJS work behind the scenes? It works through the browser itself—using only JavaScript. That’s the secret.
When you visit a website using CreepJS, the page runs scripts in your browser. These scripts don’t just read settings. They run tests. They ask your system to draw graphics, play audio, show fonts, and more. Each browser and device gives a slightly different result. That’s what makes the fingerprint unique.
This is called javascript fingerprinting techniques. It checks real behaviors, not just values. For example:
But CreepJS does more than that. It can also check if a browser is automated. Tools like Puppeteer or Playwright are used to control browsers with code. Many bots or scrapers use these tools.
So, how does CreepJS detect Puppeteer? It looks for clues. For example:
A real user moves the mouse slowly. They click on things. Their system has small quirks. Bots are fast and perfect. CreepJS sees that difference.
It compares your behavior to known patterns. If your browser acts too “clean” or “robotic,” it might not be a real user. That’s how websites use fingerprinting to block bots, even if they don’t use cookies.
So, next time you run a script in Chrome headless mode—remember, CreepJS is watching.
Because it shows you the truth.
The benefits of using CreepJS go beyond just testing. Here’s why it matters:
There are many creepjs use cases:
CreepJS is not just a tech demo. It’s a wake-up call. It helps people take control of their digital identity.
And that’s why CreepJS matters—because knowing is the first step to protecting yourself.
Curious what your browser is revealing? Let’s walk through it together. Whether you're a developer, researcher, or just curious, it’s easy to test and explore.
The fastest way to try CreepJS is through its online demo. Just visit:
👉 CreepJS Live Test
Once you open the page, the tool will scan your browser in real time. It runs tests across fingerprint categories like canvas, WebGL, fonts, screen, and more. At the end, it gives you a summary of how unique your browser is. You don’t need to install anything.2. Install CreepJS Locally
Want more control? You can run CreepJS on your own system.
You can find the full open-source code here:
👉 CreepJS GitHub Repository
To install it locally using npm:
This lets you run fingerprint tests in custom environments. It's great for automation, audits, or integrating with other tools.
This also helps when you want to compare different browsers or test headless vs. regular modes.
Let’s go through a basic example. After installing the package, you can import and run fingerprint tests in a Node.js environment. The tool will return a JSON report. You’ll see things like:
This is the core of the creepjs tutorial. You can visualize this data or export it into a report. Developers often use this to:
If CreepJS can detect your browser so well, is there anything you can do about it? The answer is yes—but it takes a few smart tools and tricks.
While there’s no perfect way to hide online, there are methods that can reduce your fingerprint uniqueness. These techniques are often used in privacy research, automation tools, and by people who care deeply about digital privacy.
The easiest way to defend against CreepJS is Dicloak. It is a browser made for multiple identities. It helps you switch between different profiles — each with a unique fingerprint. This makes it harder for tools like CreepJS to track you over time.
It’s especially useful for testing how websites behave with different device settings, or for managing multiple accounts safely.
2. Modify Fingerprint with Spoofing Techniques
More advanced users may try canvas spoofing or navigator patching. These are ways to change the values returned by fingerprint APIs.
For example:
Some browsers are built with privacy in mind. Tools like:
These tools don’t make you invisible—but they do make you harder to track. That’s a key step in creepjs fingerprint evasion.
While none of these tools guarantee full protection, they do give you more control. If you care about your online identity, these are great ways to reduce exposure and understand how to bypass creepjs in a responsible way.
Browser fingerprinting is not going away. As cookies become less useful, websites rely more on hidden ways to identify users. That’s why tools like CreepJS matter more than ever.
CreepJS is not just another browser test. It’s a powerful browser fingerprinting tool that shows what’s really happening under the hood. It gives developers, security experts, and even automation engineers a way to understand and test modern tracking methods.
So, why developers use CreepJS? Because it helps them build smarter systems.
Fingerprinting is hard to block completely. But it can be understood—and managed. That’s where creepjs for anti-fingerprinting comes in. Knowing what websites can see is the first step toward controlling it.
For the best results, use CreepJS alongside tools like:
Together, these tools help you stay ahead—whether you're protecting your privacy or building stronger bots.
CreepJS gives you the knowledge. What you do with it is up to you.
Yes, but it depends on where you live. In the U.S., laws like CCPA allow it with clear notice. In the EU, GDPR requires user consent. So browser fingerprinting is legal in many places, but privacy rules still apply.
2. Is browser fingerprinting good or bad?
That depends on how it’s used. Some websites use fingerprinting to show ads or track users, which can feel invasive. Others use it to protect accounts or stop fraud. So it can be both helpful and risky.
3. What is the difference between cookies and browser fingerprinting?
Cookies are small files saved by the browser. You can delete or block them. Fingerprinting doesn’t need files. It checks your device setup to identify you. It’s harder to block and works even in private mode.
4. What is FingerprintJS?
FingerprintJS is a commercial fingerprinting service. It helps businesses track users or stop fraud. It gives developers an API for fingerprint data.
Unlike CreepJS, FingerprintJS is made for production use. CreepJS is a free tool for testing and learning.
5. What is CreepJS?
CreepJS is an open-source tool that shows what fingerprint data your browser shares. It helps you test and understand web tracking. It’s often used by developers, testers, and privacy researchers.
6. How do I use CreepJS?
You can use it online at:
👉 https://abrahamjuliot.github.io/creepjs/
Or install it with npm:
bash | CopyEdit | npm install creepjs
You can also find the source code on GitHub:
👉 https://github.com/abrahamjuliot/creepjs
7. Can CreepJS be used on Android?
Yes. You can open the CreepJS demo in a mobile browser. But detection results may vary depending on the browser type (Chrome, Firefox, etc.).
8. Can I stop CreepJS from detecting my browser?
Not 100%, but you can reduce tracking. Try:
These tools help with creepjs fingerprint evasion, but no method is perfect.
9. What does “CreepJS fingerprint” mean?
It means the fingerprint data collected and analyzed by CreepJS. This includes:
10. Where can I find a CreepJS tutorial or example?
You can find tutorials and examples on GitHub or the main CreepJS site. Many developers also share walkthroughs online. Try searching:
“creepjs tutorial” or “creepjs example”