Browser Privacy Guide — What Your Browser Exposes and How to Fix It
The average browser scores 62 out of 100 on our privacy check — a C-minus. Most users have no idea what their browser exposes. This guide covers all 8 checks we run, what each reveals, and exactly how to fix each one.
Contents
- What the privacy score measures
- WebRTC leaks — the most commonly failed check (68%)
- Browser fingerprinting — 71% fail
- Third-party cookies — 63% still enabled
- DNS leaks — 41% fail
- Chrome vs Firefox vs Safari — who scores best?
- 3 fixes that add 33 points to your score
What the Privacy Score Measures
Our Privacy Score runs 8 checks automatically when you visit:
| Check | Pass Rate (1,000+ tests) | Severity |
|---|---|---|
| HTTPS Enforcement | 94% pass | Medium |
| DNS Leak | 59% pass | High |
| IP Geolocation Exposure | 45% pass | Medium |
| Third-Party Cookies | 37% pass | High |
| WebRTC Leak | 32% pass | Critical |
| Browser Fingerprint | 29% pass | High |
| Canvas Fingerprinting | 23% pass | High |
| Privacy Headers | 18% pass | Medium |
WebRTC Leaks — The Most Commonly Failed Check
WebRTC (Web Real-Time Communication) is a browser technology for video calls and peer-to-peer communication. The problem: it communicates directly with STUN servers to discover your local and public IP addresses — and can bypass your VPN entirely.
68% of browsers leak their real IP via WebRTC, including when using a VPN. Any website can silently run a WebRTC check and log your real IP address, rendering your VPN ineffective for hiding your location.
How to fix it:
- Firefox: Go to
about:config, search formedia.peerconnection.enabled, set it tofalse. This disables WebRTC entirely. Video calls in browser will stop working, but your IP will be protected. - Chrome: Install uBlock Origin. In the settings, enable "Prevent WebRTC from leaking local IP addresses." This blocks WebRTC IP discovery without disabling WebRTC entirely.
- Use a VPN with WebRTC protection: Mullvad, ProtonVPN, and ExpressVPN handle WebRTC at the OS level, preventing leaks even if the browser exposes it.
Test yours: anonymiz.com/webrtc-leak-test
Browser Fingerprinting — 71% Fail This Check
Browser fingerprinting identifies you by the unique combination of your browser configuration: user agent, screen resolution, installed fonts, timezone, language settings, canvas rendering, WebGL behavior, and dozens more signals. Even without cookies, this combination is often unique enough to track you across websites.
71% of browsers in our tests had unique enough fingerprints to enable cross-site tracking. The average fingerprint is derived from 18+ separate browser attributes.
How to reduce fingerprint uniqueness:
- Firefox with privacy.resistFingerprinting: Go to
about:config, enableprivacy.resistFingerprinting. This normalizes many fingerprint signals to common values. - Brave Browser: Has fingerprint randomization built in — generates slightly different fingerprints on each site, breaking cross-site correlation.
- Tor Browser: Maximum fingerprint protection. All users present an identical fingerprint, making individual identification impossible (but also causing sites to behave differently).
Check your fingerprint: anonymiz.com/browser-fingerprint
Third-Party Cookies — 63% Still Have Them Enabled
Third-party cookies are set by domains other than the one you're visiting — primarily ad networks and analytics platforms. They enable cross-site tracking: the same ad network sees you on every site that loads their scripts, building a profile of your browsing across the entire web.
Chrome delayed deprecating third-party cookies repeatedly. As of mid-2026, 63% of users still have them enabled in their browser.
How to disable them:
- Chrome: Settings → Privacy and Security → Cookies and Other Site Data → Block Third-Party Cookies
- Firefox: Enhanced Tracking Protection is on by default and blocks most third-party cookies. Set to "Strict" for maximum coverage.
- Safari: Intelligent Tracking Prevention is on by default. Most third-party cookies are blocked automatically.
DNS Leaks — 41% Fail
See our full DNS Privacy Guide for the complete explanation. Short version: your DNS queries may be going to your ISP even when you think they're private, and 41% of browsers we tested had DNS leaking.
Test: anonymiz.com/dns-leak-test
Chrome vs Firefox vs Safari — Who Scores Highest?
Based on our analysis of 1,000+ privacy scores by browser:
- Firefox with privacy settings enabled: Average 71/100 — Enhanced Tracking Protection, strict cookie handling, and about:config options give it the highest configurable ceiling
- Safari (Mac/iOS): Average 68/100 — Intelligent Tracking Prevention is solid but less configurable
- Chrome with uBlock Origin: Average 64/100 — extensions help significantly
- Chrome default settings: Average 58/100 — WebRTC exposure and third-party cookies drag it down
- Edge default: Average 56/100 — similar to Chrome default
Mobile browsers score higher than desktop (67 vs 59) because mobile operating systems restrict third-party API access more aggressively.
3 Fixes That Add 33 Points to Your Score
Fix 1 — Block WebRTC (+15 points avg). Firefox: set media.peerconnection.enabled to false in about:config. Chrome: enable WebRTC leak protection in uBlock Origin. This is the single highest-impact change.
Fix 2 — Disable third-party cookies (+10 points avg). Browser settings → Privacy → Block third-party cookies. Takes 30 seconds, immediate effect.
Fix 3 — Install uBlock Origin (+8 points avg). Blocks canvas fingerprinting attempts, eliminates many tracking scripts, reduces fingerprint surface. Available for all major desktop browsers.
These three changes can take a typical Chrome score from 58 to 91 — from F to A-.
Run your privacy score now: anonymiz.com/privacy-score — free, 10 seconds, no account.
Further reading: We analyzed 1,000 privacy scores — average is C-minus · 3 of 10 free VPNs leaked real IP via WebRTC · All privacy tools
