What’s That Sound?! is a browser extension for Chrome. It plays a sound for trackers that are loaded on websites.

You can get the Chrome Extension here.

Head’s up: the internet becomes a bit more annoying when you make tracking audible.

Why I built it

Data collection is often invisible to the end user. This makes it hard to raise awareness about it. Developments in privacy legislation have made users more aware of it through the (often notorious) cookie notification pop-ups. Besides that, most browsers are given users option to browse the internet in a more privacy friendly manner. They often default to a pretty privacy-friendly setting. The only exception here is Chrome. My assumption here is that Google’s main source of income is advertising. And privacy protection and advertising don’t easily go hand-in-hand.

I chose to use sound because it gives users a new experience. There are plenty of add blockers or pop-ups that show you what’s going on. But they limit the story in a few ways. Most don’t show you anything, they just block the ads. Others show you what trackers are active, but they often group them (e.g. ‘Google Ads’ for all Google Advertising trackers). This gives you more insights, but doesn’t tell you a lot about what’s really going on.

So my extension, What’s That Sound?!, plays a sound for each individual tracking event that occurs. By using sound, I hope users will get a better understanding of how often data of them are collected on the websites they visit.

What trackers are included?

The plug-in currently monitors all trackers by two of the biggest advertisers out there: Facebook and Google. The monitoring is based on the related entities from DuckDuckGo’s Tracker Radar (GitHub). Just so you know: this list includes 534 URLs.

Future development

The Chrome Extension is currently available as a (very) early build. I may look into a few things in the future:

  • Data Sonification Canvas: develop the idea further using the Data Sonification Canvas.
  • Sounds: change the sounds to some aspect of it (e.g. pitch) resembles the type of tracking that’s is going on. Is it collecting an email address? Is your purchase information shared? Stuff like that.

  • Platforms: add other platforms besides Facebook and Google to the setup.

And maybe some bug-fixing.


There’s is a lot to acknowledge. Between 2011 and 2020, I worked as a digital analyst for a digital marketing agency. I’ve learned a lot about tracking and privacy laws, and developed some views on data ethics during my time there.

Besides that, I saw a talk about data sonification at the S-H-O-W 2021: Impact event. A special thanks to Sara Lenzi for sharing her story.