Technical

WebGL and Canvas Fingerprinting: A Technical Deep Dive

Understand how websites use WebGL and Canvas APIs to fingerprint browsers, and how KeLAAX Stealth creates unique, consistent fingerprints.

K
KeLAAX Team
Security Research Team
January 6, 2026
14 min read
WebGL and Canvas Fingerprinting: A Technical Deep Dive

Browser fingerprinting through Canvas and WebGL represents one of the most reliable methods websites use to track visitors. Understanding these techniques is essential for anyone working with traffic automation.

Technical Note: This article covers advanced browser internals. Basic understanding of web technologies is helpful but not required.


What is Browser Fingerprinting?

Browser fingerprinting is the practice of collecting browser and device characteristics to create a unique identifier without using cookies.

Fingerprinting vs Cookies

AspectCookiesFingerprinting
StorageClient-sideServer-side
ClearableYesNo
User consentOften requiredRarely asked
AccuracyVery highHigh
PersistenceUntil clearedPermanent

Canvas Fingerprinting Explained

How It Works

The HTML5 Canvas API allows websites to render graphics in the browser. Here's the key insight:

The Fingerprint: Due to differences in graphics hardware, drivers, and rendering engines, the exact same drawing commands produce slightly different pixel values across different systems.

The Process

  1. Website creates hidden canvas element
  2. Draws complex graphics (text, shapes, gradients)
  3. Extracts pixel data using toDataURL()
  4. Hashes the result into a fingerprint
Canvas Fingerprint Factors
FactorImpact
GPU modelHigh
GPU driverHigh
OS renderingMedium
Font renderingMedium
AntialiasingMedium

Detection Accuracy

Canvas fingerprinting alone can identify:

Browser ConfigurationUnique Fingerprints
Desktop browsers~91% unique
Mobile browsers~85% unique
Same hardwareVery similar

WebGL Fingerprinting Explained

WebGL provides even more fingerprinting opportunities through 3D graphics capabilities.

WebGL Information Exposed

Renderer Information

ParameterExample Value
VendorGoogle Inc. (NVIDIA)
RendererANGLE (NVIDIA GeForce RTX 3080)
VersionWebGL 2.0 (OpenGL ES 3.0)
Shading LanguageWebGL GLSL ES 3.00

Critical Exposure: The WebGL renderer string often reveals exact GPU model and driver version—highly unique information.

WebGL Fingerprint Methods

Method 1: Parameter Collection

Websites query dozens of WebGL parameters:

CategoryParameters Collected
LimitsMax texture size, viewports
FeaturesSupported extensions
PrecisionFloat/int precision
RendererGPU vendor/model
Method 2: Render Tests

Similar to canvas, websites render WebGL scenes and analyze:

  • Pixel values
  • Rendering precision
  • Anti-aliasing patterns
  • Shader outputs

Why Simple Spoofing Fails

Many tools attempt to spoof these fingerprints by:

  1. Returning fake renderer strings
  2. Adding random noise to canvas
  3. Blocking API access entirely

Problems with These Approaches

ApproachDetection Method
Fake stringsInconsistent with other signals
Random noiseChanges between calls
API blockingMissing expected data

Detection Reality: Sophisticated systems check for fingerprint consistency. If your canvas fingerprint changes between calls, or doesn't match your reported GPU, you're flagged instantly.


How KeLAAX Stealth Handles Fingerprinting

The Consistent Profile Approach

KeLAAX Stealth creates fingerprints that are:

Key Characteristics
CharacteristicImplementation
Unique21,000+ distinct profiles
ConsistentSame fingerprint across all calls
RealisticBased on real hardware data
CompleteAll APIs return matching data

Canvas Spoofing Method

Our approach injects deterministic noise based on the profile:

The Secret: Instead of random noise (detectable), we use a seeded noise pattern that produces the same result every time for that profile, but different results across profiles.

Noise Injection Process

  1. Profile generates unique noise seed
  2. Seed determines pixel-level adjustments
  3. Same seed = same adjustments = consistent fingerprint
  4. Different profile = different seed = unique fingerprint

WebGL Spoofing Method

For WebGL, we implement a more sophisticated approach:

ComponentSpoofing Method
Renderer StringRealistic GPU replacement
ParametersHardware-consistent values
Render OutputSeeded noise matching profile
ExtensionsPlatform-appropriate list
Renderer String Generation

We maintain a database of real GPU configurations:

Profile TypeExample Renderer
High-end PCNVIDIA GeForce RTX 4090
Mid-range PCNVIDIA GeForce GTX 1660
MacApple M1 Pro
IntegratedIntel UHD Graphics 630

Advanced Fingerprint Consistency

Cross-API Consistency

Modern detection checks if fingerprints are consistent across APIs:

Consistency Check: If your Canvas fingerprint suggests an NVIDIA GPU but your WebGL renderer claims AMD, detection is certain.

What Must Match

SignalMust Match With
Canvas hashWebGL renderer
GPU stringsScreen resolution
CPU coresPerformance benchmarks
Font listOS platform

KeLAAX Stealth's Profile System

Each profile includes coordinated values:

Complete Profile Example
ComponentValue
Canvas Hash[Unique per profile]
WebGL RendererNVIDIA GeForce RTX 3070
Screen2560x1440
CPU Cores8
PlatformWin32
Font Count147

Testing Your Fingerprint

Recommended Testing Sites

SiteTests
BrowserLeaksComprehensive
AmIUniqueComparison data
CreepJSAdvanced detection
PixelscanBot detection

What to Look For

Green Flags
  • Consistent fingerprint across page loads
  • Fingerprint matches profile configuration
  • No JavaScript errors in console
  • All APIs return realistic values
Red Flags
  • Fingerprint changes between calls
  • Mismatched hardware signals
  • Blocked or undefined API responses
  • Fingerprint matches known bot profiles

Conclusion

Canvas and WebGL fingerprinting are sophisticated tracking techniques that require equally sophisticated countermeasures. Simple spoofing approaches fail because they prioritize randomization over consistency.

KeLAAX Stealth's approach—unique, consistent, realistic fingerprints—provides the authenticity needed to avoid detection while maintaining the diversity required across multiple profiles.

Your browser fingerprint tells a story. Make sure each profile tells a believable, unique story that matches all its other characteristics.

Ready to try KeLAAX Stealth?

Start your 7-day free trial and experience undetectable traffic generation with 21,000+ unique browser profiles.