What Is Browser Fingerprinting?
Browser fingerprinting is a tracking technique that identifies you based on the unique combination of properties your browser and device expose. Unlike cookies, it stores nothing on your device — instead, it reads data that your browser freely provides to every website you visit.
The result is a digital fingerprint that can identify you across different websites, sessions, and even after clearing your cookies and history. Use our Browser Fingerprint Checker to see exactly what data your browser reveals right now.
What Data Does Browser Fingerprinting Collect?
- Canvas fingerprint — Your GPU renders text and shapes slightly differently from every other device. The resulting image hash is almost universally unique.
- WebGL fingerprint — Your graphics card's renderer string and vendor identify your hardware at a granular level.
- Screen resolution & colour depth — Reveals your monitor setup.
- Installed fonts — The specific combination of fonts installed on your system is highly unique.
- Timezone & language — Combined with location data, these narrow down who you are significantly.
- User-Agent string — Reveals your OS version, browser version, and rendering engine.
- Hardware concurrency — The number of CPU cores your device has.
- Battery status — Even your current battery level has been used as a tracking signal.
- Audio context fingerprint — How your browser processes audio creates another unique signal.
How Is Fingerprinting Different from Cookies?
Cookies are stored on your device and can be deleted. Browser fingerprints are stateless — nothing is written to your computer. Every time you visit a site, your browser involuntarily broadcasts the same identifying information. Clearing cookies, using private mode, or switching browsers does not help.
This makes fingerprinting significantly more persistent than cookie-based tracking.
Who Uses Browser Fingerprinting?
- Ad networks — To track you across websites for targeted advertising even after you clear cookies.
- Fraud detection — Banks and payment processors use fingerprinting to identify suspicious account behaviour.
- Paywalls — News sites use fingerprinting to enforce article limits across incognito sessions.
- Security systems — To detect bots and automated scraping tools.
How to Protect Against Browser Fingerprinting
- Use Tor Browser — Standardises all fingerprint signals so every Tor user looks identical. Most effective protection available.
- Use Brave Browser — Randomises canvas, WebGL, and audio fingerprints on every page load. Built-in, no extension needed.
- Firefox with resistFingerprinting — Go to about:config and set privacy.resistFingerprinting to true. Spoofs many fingerprint signals.
- Canvas Blocker extension — Adds noise to canvas and WebGL readings. Available for Firefox and Chrome.
- Avoid rare configurations — Unusual screen sizes, rare fonts, or exotic browser settings make you more unique, not less. Blend in.
Check Your Own Browser Fingerprint
Our free Browser Fingerprint Checker shows your canvas hash, WebGL renderer, all exposed system properties, and gives you a privacy score from 0 to 100. You can see exactly which signals are leaking and get specific recommendations to improve your score.
Related Privacy Tools
- WebRTC Leak Test — Check if your VPN leaks your real IP
- What Is My IP — See your public IP and location data
- HTTP Headers Checker — See all headers your browser sends
- Dereferer — Share links without exposing your source