Browser Fingerprinting: What It Is & How to Stop It

Summary

Browser fingerprinting collects unique characteristics of your browser and device to identify you, even without cookies. It combines screen size, fonts, plugins, timezone, and more to create a unique “fingerprint.” Protect yourself with privacy browsers, fingerprinting resistance, and anti-tracking tools.

What is Browser Fingerprinting?

Browser fingerprinting is a tracking method that identifies you by collecting unique characteristics of your browser and device. Unlike cookies, fingerprints can’t be easily deleted and work across different websites.

How It Works

1. Website loads JavaScript code
2. Code collects browser characteristics:
   • Screen resolution
   • Installed fonts
   • Browser plugins
   • Timezone
   • Language settings
   • Hardware information
   • Canvas fingerprint
   • WebGL fingerprint
3. Characteristics combined into unique fingerprint
4. Fingerprint used to track you across sites

Why It’s Effective

• Unique: Your combination of characteristics is likely unique
• Persistent: Doesn’t rely on cookies or storage
• Hard to avoid: Works even with privacy settings
• Cross-site: Tracks you across different websites

What Gets Collected

Screen and Display

• Screen resolution
• Color depth
• Pixel ratio
• Available screen space

Fonts

• Installed fonts list
• Font rendering characteristics
• System fonts available

Browser Information

• User agent string
• Browser version
• Operating system
• Platform information

Plugins and Extensions

• Installed plugins
• Extension list (sometimes)
• MIME types supported

Hardware

• CPU cores
• Memory information
• Device type
• Touch support

Behavioral

• Typing patterns
• Mouse movements
• Scrolling behavior
• Interaction timing

Advanced Techniques

• Canvas fingerprinting: Renders hidden image, unique rendering creates fingerprint
• WebGL fingerprinting: Uses graphics card characteristics
• Audio fingerprinting: Uses audio processing characteristics
• Battery API: Battery level and charging status

How Unique Are You?

Research Findings

• Basic fingerprint: 1 in 286,777 browsers
• With canvas: 1 in 2,190,000 browsers
• With advanced techniques: Often unique

Factors That Make You Unique

• Uncommon screen resolution
• Rare font combinations
• Unusual browser configuration
• Custom extensions
• Non-standard settings

How to Prevent Fingerprinting

1. Use Privacy-Focused Browsers

Tor Browser: - Maximum fingerprinting protection - All users look similar - Blocks many fingerprinting techniques - Slower but most private

Firefox with Privacy Settings: - Enable “Resist Fingerprinting” in about:config - Use strict tracking protection - Install privacy extensions - Good balance of privacy and usability

Brave Browser: - Built-in fingerprinting protection - Blocks many tracking techniques - Good defaults - Fast and private

Mullvad Browser: - Based on Firefox - Hardened for privacy - Strong fingerprinting resistance - Good for privacy-conscious users

2. Browser Settings

Firefox: 1. Go to about:config 2. Set privacy.resistFingerprinting to true 3. Set privacy.trackingprotection.enabled to true 4. Use strict tracking protection

Chrome/Edge: - Limited native fingerprinting protection - Use extensions (uBlock Origin, Privacy Badger) - Consider switching to privacy browser

Brave: - Fingerprinting protection enabled by default - Can be adjusted in Shields settings - Good out-of-the-box protection

3. Browser Extensions

uBlock Origin: - Blocks tracking scripts - Reduces fingerprinting data collection - Free and open source - Highly recommended

Privacy Badger: - Learns and blocks trackers - Reduces fingerprinting - EFF-developed - Good complement to uBlock

Canvas Blocker: - Blocks canvas fingerprinting - Firefox extension - Prevents canvas-based tracking

4. Advanced Techniques

Use Tor Browser: - Maximum anonymity - All users look similar - Blocks most fingerprinting - Best for high-privacy needs

Disable JavaScript: - Blocks most fingerprinting - Breaks many websites - Use selectively (NoScript)

Use VPN + Privacy Browser: - Hides IP address - Reduces tracking - Good combination - Not perfect but helpful

Testing Your Fingerprint

Online Tools

AmIUnique.org: - Shows your browser fingerprint - Compares to other users - Shows uniqueness score - Educational tool

BrowserLeaks.com: - Comprehensive fingerprinting test - Shows what’s being collected - Tests various techniques - Good for understanding exposure

Cover Your Tracks (EFF): - Tests fingerprinting resistance - Shows tracking protection level - Provides recommendations - Privacy-focused

What to Look For

Good signs: - Low uniqueness score - Common fingerprint - Limited data collection - Fingerprinting blocked

Bad signs: - High uniqueness score - Rare fingerprint - Extensive data collection - Fingerprinting active

Best Practices

For Maximum Protection:

1. Use Tor Browser for sensitive browsing
2. Enable fingerprinting resistance in Firefox
3. Use privacy-focused browsers (Brave, Mullvad)
4. Install anti-tracking extensions
5. Disable unnecessary browser features

For Balanced Protection:

1. Use Firefox with privacy settings
2. Enable “Resist Fingerprinting”
3. Install uBlock Origin
4. Use Privacy Badger
5. Keep browser updated

General Tips:

1. Don’t install unnecessary extensions
2. Use standard browser settings when possible
3. Keep browser updated
4. Use privacy-focused browsers
5. Test your fingerprint regularly

Limitations

Complete Prevention is Difficult

Why: - Many techniques exist - New methods developed constantly - Some fingerprinting is inevitable - Balance privacy with usability

Reality: - Can reduce fingerprinting significantly - Can’t eliminate it completely - Tor Browser offers best protection - Most users need balanced approach

Browser-Specific Guidance

Firefox

• Enable privacy.resistFingerprinting
• Use strict tracking protection
• Install uBlock Origin
• Use Privacy Badger
• Consider Tor Browser for maximum privacy

Chrome/Edge

• Limited native protection
• Use extensions (uBlock Origin)
• Consider switching to privacy browser
• Use Brave if staying with Chromium

Brave

• Good defaults
• Fingerprinting protection enabled
• Can adjust in Shields
• Good balance of privacy and speed

Tor Browser

• Maximum protection
• All users look similar
• Best for anonymity
• Slower but most private

Common Questions

Q: Can I completely prevent fingerprinting? A: Complete prevention is difficult, but you can significantly reduce it with privacy browsers and settings.

Q: Does private/incognito mode prevent fingerprinting? A: No, private mode only prevents local storage. Fingerprinting still works.

Q: Will a VPN prevent fingerprinting? A: VPNs hide your IP but don’t prevent browser fingerprinting. Use both for better protection.

Q: Which browser is best for preventing fingerprinting? A: Tor Browser offers the best protection, followed by Firefox with privacy settings and Brave.

Q: Do extensions help? A: Yes, extensions like uBlock Origin and Privacy Badger can significantly reduce fingerprinting.

Conclusion

Browser fingerprinting is a sophisticated tracking method that’s hard to avoid completely. However, you can significantly reduce it by using privacy-focused browsers, enabling fingerprinting resistance, and installing anti-tracking extensions.

For most users, Firefox with privacy settings or Brave Browser offer good protection with usability. For maximum protection, use Tor Browser for sensitive browsing.

Remember: Fingerprinting is just one tracking method. Combine fingerprinting protection with other privacy tools (VPNs, ad blockers, privacy browsers) for comprehensive protection.

Start by testing your fingerprint at BrowserLeaks.com, then enable privacy settings in your browser and install anti-tracking extensions.