SEO title: Understanding CreepJS: Your Guide to Bypassing Browser Fingerprinting
SEO dEscription: Learn how CreepJS can help you bypass browser fingerprinting and enhance your online privacy. Discover practical tips in our comprehensive guide.
(1)CreepJS: Browser Fingerprinting Tests, Detection, and How Undetectable.io Helps You Pass
If you manage multiple accounts across platforms like Google, Facebook, TikTok, or Amazon, you’ve probably heard whispers about CreepJS. This open-source browser fingerprinting project is widely used as a public diagnostic reference for testing browser fingerprint consistency and anti-fingerprinting leaks.
In this guide, we’ll break down exactly what CreepJS does, how it exposes browser fingerprinting techniques used by anti-bot systems, and how tools like Undetectable.io help you build profiles that pass these tests consistently.
Quick Summary: What CreepJS Is and Why It Matters in 2026
CreepJS is a public browser fingerprint testing suite used by anti-bot researchers, scrapers, and privacy-conscious developers. You can access it at https abrahamjuliot.github.io creepjs to see exactly how unique and suspicious your browser environment looks.
In plain terms, CreepJS reveals how much identifying data your browser exposes and highlights inconsistencies, tampering signals, and patterns often associated with modified or automated environments. It flags headless detection signals, spoofing attempts, and inconsistencies that real anti-bot systems also catch. The tool performs entropy analysis on collected data to determine how rare your configuration is compared to typical web browsers.
As of 2026, many anti-bot systems use fingerprinting and consistency checks that overlap with the kinds of signals surfaced by CreepJS, although CreepJS itself is not a direct model of any one commercial system. Performing well on this test can be a useful diagnostic signal, but it is not a reliable standalone measure of real-world undetectability.
At Undetectable.io, we use CreepJS-style tests internally to tune our profile templates. This ensures that users running multi-account work, ad arbitrage, or traffic campaigns start with fingerprints that don’t raise red flags.
What Is CreepJS?
CreepJS is an open-source JavaScript browser fingerprinting library and public demo site that inspects hundreds of browser attributes. It probes everything from navigator properties and WebGL parameters to installed fonts and screen properties—building a comprehensive picture of your device properties.
Unlike commercial trackers, CreepJS functions as a research and diagnostic tool. Security researchers, scraping developers, and privacy advocates use it to evaluate anti fingerprinting extensions, hardened browsers, and browser automation tools. It’s not tracking you for advertising; it’s showing you exactly what advertisers could track.
The tool highlights “lies” or inconsistencies created by anti fingerprinting tools. For example, if your user agent strings claim macOS but your GPU and fonts look like Windows, CreepJS flags this as javascript tampering.
Since around 2021, CreepJS has been actively referenced in scraping and security communities. In 2026, it remains one of the most widely referenced public tools for testing browser fingerprint consistency and anti-fingerprinting leaks.
CreepJS produces visual reports with scores including headless detection ratings, trust scores, and detailed lists of anomalies. These reports reveal exactly which browser behaviors expose your automated or modified browser environment.
How CreepJS Works Under the Hood
At its core, CreepJS executes comprehensive JavaScript probes across numerous browser apis. It queries the Navigator API, Canvas, WebGL, Web Audio API, Screen API, Fonts, DOM, WebRTC, and more—collecting raw fingerprint data from each.
The sophisticated browser fingerprinting tool combines these values using hashing algorithms to create unique fingerprints. It then estimates entropy—measuring how rare your configuration is compared to normal user distributions. High-entropy signals like complex rendering capabilities carry more weight than common data points.
CreepJS calculates a “trust score” that reflects how consistent and believable the reported fingerprint values appear. The more inconsistencies it finds—mismatched properties, suspicious behavior patterns, detected modifications—the lower your score drops. A low trust score indicates likely automation or spoofing.
The tool also logs console errors, timing quirks, and rendering differences prevalent in headless environments. If your browser renders graphics using software instead of hardware acceleration, CreepJS notices. If your audio stack details look stripped down, that’s flagged too.
CreepJS receives frequent updates to probe new browser apis introduced in modern Chromium, Firefox, and Safari releases. This means the fingerprinting process evolves alongside the browsers it tests.
Main Fingerprinting Vectors Measured by CreepJS
CreepJS doesn’t rely on a single signal. Instead, it layers many fingerprinting techniques for robust identification. This multi-signal approach mirrors how real anti bot detection systems work.
The core categories include:
- Navigator and user agent properties
- WebGL and Canvas rendering
- Audio, speech, and media capabilities
- Screen, display, and layout signals
- Fonts, DOM behavior, and other data points
Optimizing across these categories improves survival on platforms using similar fraud detection methods.
Navigator and User Agent Properties
CreepJS queries window.navigator fields extensively. Key properties include:
| Property | What It Reveals |
| userAgent | Browser version and operating system |
| platform | Claimed OS platform |
| hardwareConcurrency | Logical CPU cores |
| deviceMemory | RAM available to browser |
| webdriver | Automation flag |
| languages | Locale preferences |
Combinations matter. A profile claiming “Windows 10, en-US, 8 logical cores, Chrome 122” gets statistically profiled against known distributions. Unnatural combinations trigger suspicion.
The navigator.webdriver flag directly exposes Selenium, Playwright, or Puppeteer automation unless properly patched. This single property causes near-instant detection for unmodified browser automation tools.
Crude spoofing fails here. Claiming macOS while your GPU reports Windows hardware details creates contradictions that creepjs detects immediately.
WebGL and Canvas Rendering
CreepJS draws shapes, text, and 3D scenes using Canvas 2D and the web graphics library (WebGL) to fingerprint your GPU. It captures:
- GPU vendor and model (e.g., Intel UHD Graphics 620 vs. NVIDIA GeForce RTX 3060)
- Driver quirks and supported extensions
- Pixel-level rendering differences
- Anti-aliasing behavior
Software rendering—common in naive headless Chrome—looks distinctly different from hardware-accelerated output. Creepjs effectively creates a hash of how your browser renders graphics, penalizing obvious automation signatures.
Even two laptops running the same browser version produce different Canvas hashes due to subtle hardware details. This makes webgl parameters extremely high-entropy for identifying unique browser fingerprints.
Audio, Speech, and Media Capabilities
CreepJS uses the web audio api and media capability queries to probe your audio stack details. It checks:
- Supported codecs (AAC, Opus, etc.)
- Sample rates and latency
- Available output devices
- Speech synthesis voices and languages
A regular Windows 11 Chrome installation shows full codec support. A stripped-down headless build often lacks several codecs—a telltale sign of automation.
Audio fingerprinting catches unusual stacks common in containers or VMs. If you’re running multi-account operations on RDP sessions or cloud instances, missing audio signals can correlate your profiles as suspicious.
Screen, Display, and Layout Signals
CreepJS fingerprints display properties including:
- Client screen resolution
- Color and pixel depth
- devicePixelRatio
- Available viewport sizes
- CSS media queries
Natural resolutions follow predictable patterns:
| Device Type | Common Resolutions |
| Desktop | 1920×1080, 2560×1440 |
| Laptop | 1366×768, 1920×1080 |
| Mobile | 390×844, 412×915 |
Odd or obviously emulated screen resolution values signal automation. Scaling mismatches—where devicePixelRatio doesn’t fit the reported OS DPI—indicate virtualization.
Automation frameworks sometimes misalign window.innerWidth/innerHeight with reported screen properties, which CreepJS flags as anomalies.
Fonts, DOM Behavior, and Other High-Entropy Data
CreepJS inspects installed fonts, CSS feature support, DOM quirks, and error messages. Font lists differ dramatically across systems:
- Stock Windows 11 includes specific Microsoft fonts
- macOS Sonoma has Apple system fonts
- Linux distros vary widely by distribution
These variations create strong identifiable fingerprint signatures. Privacy-focused browsers that block font enumeration sometimes create their own anomalies that CreepJS labels as tampering.
Console error signatures also matter. Specific stack traces from installed plugins or automation libraries expose Puppeteer, Selenium, or Playwright usage—even when other properties are patched.
These “long tail” signals matter for data collection on platforms like Meta Ads, Google Ads, TikTok, and marketplaces like Amazon, and they’re a key factor when comparing GoLogin alternatives for multi-accounting and other antidetect browsers.
Testing Browser Automation and Scrapers on CreepJS
Developers and growth teams routinely test their automation tools on CreepJS before deploying at scale. The results reveal exactly how detectable their setups are.
Common test scenarios include raw headless environments often show obvious anomalies, while stealth-patched or hardened environments may reduce them—but the exact result varies significantly by browser version, OS, hardware, and patch quality.
A “good” result means low headless suspicion, minimal inconsistencies, and fingerprints resembling typical end-user machines.
Running Classic Headless Browsers (Selenium, Playwright)
Launching a standard headless Chromium instance with Selenium or Playwright and navigating to CreepJS typically produces devastating results:
- webdriver flag = true
- Missing installed fonts
- Software WebGL rendering
- Odd screen resolution (often 1366×768 in CI/VMs)
- Near-100% headless detection score
These findings translate directly to rapid throttling by real-world anti-bot systems. In many CI and VM environments, headless Chromium setups often expose patterns such as software rendering, missing fonts, or automation flags, although exact results vary by configuration.
The practical impact is clear: unmodified web scraper setups get flagged and blocked almost immediately on platforms with fingerprinting tools deployed.
Using Stealth Plugins and Patched Drivers
Communities maintain stealth plugins like undetected-chromedriver and Playwright/Puppeteer stealth modes. These attempt to patch telltale properties including the webdriver flag and default settings.
CreepJS typically shows improved scores with stealth plugins, but patterns persist:
- Unnatural font sets
- Inconsistent audio stack
- Rare GPU combinations
- Prototype modifications
These open-source patches require constant updates as Chrome, Firefox, and CreepJS evolve. Through 2024-2026, each browser update potentially reintroduces leaks.
While stealth plugins help, they’re often insufficient for stable, large-scale multi-account work or ad arbitrage. Patches alone are often insufficient for stable results, especially as browsers and fingerprint tests continue to evolve.
How Undetectable.io Uses CreepJS-Style Signals to Build Better Profiles
At Undetectable.io, we’ve built an antidetect browser designed for high-anonymity multi-accounting across platforms like Google, Facebook, TikTok, Amazon, and various marketplaces, available for download on Windows and macOS.
Instead of patching a single headless browser, we generate full browser profiles with coherent fingerprints that score naturally on tools similar to CreepJS. Each profile represents a plausible user’s device—not a Frankenstein of spoofed properties.
Two key differentiators set us apart:
- Unlimited local profiles on any paid plan—create hundreds or thousands without cloud limitations
- Local storage of fingerprints and stored site data on your device, minimizing leak risks
Our team continuously validates profile templates against public fingerprint test suites, including CreepJS-like checks. This catches inconsistencies before our users encounter them in production.
Consistent, Non-Contradictory Fingerprints
Undetectable.io ensures internal consistency across all various browser attributes. Operating system version, GPU, fonts, screen resolution, and navigator properties align to look like real device types.
Example profile templates include:
- US-based Windows 11 + Chrome with 1920×1080 screen and Intel UHD graphics
- macOS Sonoma + Safari-like profile with Retina scaling
- European Windows 10 + Firefox with 1366×768 laptop resolution
This coherence eliminates the contradictions CreepJS flags—no macOS user agent with Windows fonts, no mismatched WebGL vendor strings. The same fingerprint consistency makes profiles harder to separate from real users in fingerprint creation databases.
Mass Profile Creation and Proxy Management for Multi-Accounting
Undetectable.io lets users mass-create hundreds or thousands of profiles, each with unique fingerprints and proxy settings. You can assign residential, mobile, or datacenter proxies per profile.
Why this matters for creepjs detection: reusing the same fingerprint across many accounts creates obvious clusters. Varied profiles with unique configurations blend into normal user distributions.
Our interface supports:
- Per-profile proxy assignment
- Timezone and geo adjustment
- Regional browser features alignment
- Bulk import/export workflows
Teams running ad campaigns, airdrops, traffic arbitrage, dropshipping stores, and social media farming rely on this fingerprint diversity to avoid clustering.
Cookies Robot, Warm-Up, and Behavioral Realism
Beyond static fingerprints, Undetectable.io includes a cookies robot to simulate browsing sessions and build natural-looking histories. Fresh profiles with no other stored site data look suspicious to anti-bot systems.
CreepJS focuses on technical fingerprints, but real platforms combine fingerprinting with behavioral patterns—session age, cookies, navigation flows. Disabling javascript or avoiding warm-up leaves obvious gaps.
Warming up profiles by visiting news sites, search engines, and normal websites before accessing ad platforms reduces suspicion. This pre-population mimics how real users browse.
Fingerprint stealth plus realistic history plus quality proxies—this combination is essential for online security in 2026’s fingerprint-heavy ecosystem.
Strategies to Reduce CreepJS Detection (and Real Anti-Bot Detection)
No single step guarantees invisibility. A layered approach significantly lowers detection risks while maintaining operational stability.
Core strategy areas:
- Coherent, realistic fingerprints
- Diverse infrastructure and proxies
- Careful browser automation hygiene
- Continuous testing and validation
Important: Always comply with platform terms, laws, and local regulations when using stealth or automation techniques.
Align Technical Fingerprints with Realistic Device Profiles
Avoid random, contradictory spoofing. Use structured profiles mapping to plausible devices and locations.
Key alignments:
- Match proxy geo with reported timezone
- Align GPU type with claimed operating system
- Use font sets typical for your reported region/OS
- Ensure hardware details match expected configurations
This alignment directly improves results on CreepJS-like tests by reducing obvious anomalies. Undetectable.io’s templates enforce this coherence by default.
Use Dedicated Proxies and Isolated Profiles
Assign separate, high-quality proxies to distinct profiles and accounts. IP reputation combines with CreepJS-style fingerprints to form risk scores.
Best practices:
- Residential or mobile proxies for sensitive platforms
- One proxy per account where possible
- Geographic consistency between IP and profile
You can compare and choose providers using our guide to the best proxy services for multi-accounting and arbitrage.
Undetectable.io’s per-profile proxy management simplifies maintaining isolation at scale—whether you’re running 50+ Facebook accounts, multiple Google Ads projects, or marketplace seller accounts across regions.
Automate Carefully and Mimic Real User Behavior
Perfect fingerprints fail if automation behavior appears robotic. Platforms log UX signals alongside technical checks.
When using APIs or external automation:
- Add random delays between actions
- Include realistic scrolling and mouse movement
- Vary navigation paths
- Simulate reading time and interaction diversity
Undetectable.io works with external automation tools via API. Pair our fingerprint stealth with behavioral realism for maximum survival rates.
Continuously Test Against Public Fingerprinting Suites
Regularly test setups on CreepJS and alternative creepjs-similar pages like BrowserLeaks.com. Browser and OS updates can reintroduce leaks—Chrome major versions in 2025-2026 have already shifted detecting algorithms multiple times.
Operational best practices:
- Maintain “canary” profiles for testing changes
- Verify profiles before deploying to production accounts
- Document which browser version each profile template targets
- Roll updates gradually across your fleet
This approach catches regressions before they affect your campaigns.
Limitations of CreepJS and Why You Shouldn’t Rely on It Alone
CreepJS is powerful but not identical to commercial anti-bot systems. Real platforms combine fingerprinting with:
- Login history and payment data
- Behavioral modeling across sessions
- Cross-device correlation
- Python script detection and API abuse patterns
Some CreepJS detections may be stricter than production environments. Other real-world checks—proprietary behavioral analysis, account history scoring—aren’t visible in its UI.
CreepJS is a valuable indicator through its extensive probing capabilities, but not the sole arbiter of account safety. Tools like Whoer.net for anonymity checking help reveal IP, DNS, and WebRTC leaks that CreepJS doesn’t cover. At Undetectable.io, we focus on broader operational success across platforms, not just passing one test page.
Using Undetectable.io to Stay Ahead of CreepJS-Style Detection
CreepJS exposes fingerprint weaknesses that real anti-bot systems also exploit, which is why some teams also rely on specialized cloaking services for campaign protection:
- Navigator flags and automation markers
- WebGL/Canvas rendering discrepancies
- Unusual audio signals and screen setups
- Font enumeration anomalies and privacy-resistance patterns commonly associated with hardened browsers
Undetectable.io addresses these through:
- Coherent profile templates matching real device configurations
- Unlimited local profiles for fingerprint diversity
- Per-profile proxy management for IP isolation
- Cookies robot for building realistic browsing sessions
- Team synchronization for agency workflows
Start with our free and paid pricing plans on Undetectable.io to experiment. Create a few profiles, run them on CreepJS and real platforms, then scale successful setups across your campaigns.
Ready to build profiles that pass CreepJS-style detection? Start for free with Undetectable.io and harden your multi-account infrastructure before launching your next campaign.