You Are Being Followed

Every time you visit a website, dozens of invisible third parties may be recording your visit. They note which pages you read, how long you stayed, where you clicked, and what you searched for. Then they follow you to the next site, and the next. Over time, this data builds a detailed profile of your interests, habits, and behaviors — all without your meaningful consent.

Understanding how this tracking works is the first step toward stopping it.

The Main Types of Online Trackers

1. Third-Party Cookies

The most well-known tracking method. When you visit a website that embeds a Facebook "Like" button or a Google ad, those companies set a cookie in your browser. The next time you visit any other site with the same embedded content, that cookie identifies you, linking your visits across unrelated sites.

2. Tracking Pixels

A tracking pixel is a tiny (often 1×1 pixel) invisible image embedded in a webpage or email. When your browser loads it, it sends your IP address, device type, and timestamp to the tracker's server. Email newsletters commonly use these to know if you opened an email.

3. Link Decoration / URL Parameters

You may have seen URLs with long strings like ?fbclid=ABC123 or ?utm_source=email. These parameters pass identifying information about you from one site to another, allowing trackers to connect your sessions even without cookies.

4. Session Replay Scripts

Some sites embed scripts that record your exact mouse movements, scrolling, and keystrokes — essentially a video recording of your entire session. This data is sent to analytics companies like Hotjar or FullStory for "user experience research."

5. Supercookies and Evercookies

These are tracking identifiers stored in unusual places (browser cache, IndexedDB, localStorage, ETags) that persist even after you clear your regular cookies. They can "respawn" a tracking cookie you deleted.

6. Browser Fingerprinting

As covered in our fingerprinting guide, this technique identifies your device by its unique combination of technical characteristics — no cookie or storage required.

Who Is Doing the Tracking?

Tracking isn't just done by the sites you visit. Much of it comes from third-party companies whose code is embedded across thousands of websites:

  • Google Analytics / Google Ads — present on a majority of websites globally
  • Meta Pixel (Facebook) — tracks conversions and user behavior for ad targeting
  • Amazon Advertising — tracks browsing to serve product ads
  • Data brokers — aggregate data from multiple sources to build and sell profiles

How to Block Trackers Effectively

Step 1: Use a Content Blocker

uBlock Origin with the EasyPrivacy filter list blocks the vast majority of known tracking scripts. Enable it in the extension's dashboard under "Filter Lists → Privacy."

Step 2: Enable Your Browser's Built-In Protection

  • Firefox: Set Enhanced Tracking Protection to Strict mode (Settings → Privacy & Security)
  • Brave: Enable Shields and set to Aggressive mode
  • Safari: Enable Intelligent Tracking Prevention (on by default)

Step 3: Clear URL Tracking Parameters

Firefox's Query Parameter Stripping feature (enabled in Strict ETP mode) automatically removes tracking parameters like fbclid and gclid from URLs. The ClearURLs extension does the same for Chrome.

Step 4: Use a Privacy-Respecting DNS

DNS resolvers like Cloudflare 1.1.1.1 or NextDNS can block tracker domains at the network level before your browser even makes a connection.

Step 5: Consider a VPN

A VPN hides your real IP address, making IP-based tracking harder. It also encrypts your traffic from your ISP. Choose a VPN with a verified no-logs policy.

A Realistic Expectation

No tool blocks 100% of tracking. New techniques emerge constantly, and some tracking (like server-side analytics) is invisible to browser extensions. But combining a privacy-focused browser, a content blocker, and good DNS settings blocks the overwhelming majority of commercial tracking and makes building a profile on you significantly harder.

Start with the basics, and add layers of protection as you get comfortable with each tool.