Browser History Audit

Inspiration

You can feel the web watching you, but you can't see it. An ad that's too accurate. A phishing email that knows what you bought last week. EFF has been measuring this for years; their Privacy Badger scans record which third-party domains track users across popular sites. It's one of the most important records of online surveillance in existence. It also lives in a SQLite file that requires SQL to query. That gap, between a dataset that proves a problem and the people who live the problem, is what we wanted to close. Not with a dashboard for analysts. By meeting users in the moment they're being tracked.

What it does: Our solution is a browser extension that augments Privacy Badger with bite-sized lessons drawn from EFF's tracker dataset. When you open a site, it:

Surfaces the third-party trackers loading on the page Shows how the data is being used Visualizes the trend over time Tells what to do now that you know you are being tracked.

Every claim is linked back to the underlying EFF data.

How we built it: EFF SQLite → Pre-computed JSON → Browser extension → In-context lesson

Challenges we ran into: 1. Understanding our user base. 2. Assumption of user background led us into many use cases that were not the best solution.

Accomplishments that we're proud of: 1. Every claim is sourced and dated. 2. Transparency to users. 3. Building a solution that novice users can interact with

What we learned: 1. Plain language is harder than it looks. 2. Assuming the background of a user is a big mistake.

What's next for Browser History Audit: 1. A path to merge into Privacy Badger itself. 2. A focus mode, for users with specific browsing needs.

Built With

• chrome
• claude-code
• css
• html
• javascript
• json
• sqlite