Data Warehouse: Tracking Pixel

Illustration by Giorgia Lupi

What is a Tracking Pixel?

Tracking pixels, aka Marketing pixels, are essentially these tiny snippets of code that allow you to gather information about visitors on a website — how they browse, what type of ads they click on, etc. This behavior data helps you send the user paid ads that are likely to be most interesting to them.

The term “pixel” is short for “Picture Element”, the images on the computer display contain these tiny dots. Then, Tracking pixels are 1×1 pixel large, usually transparent graphics that are integrated into the respective website.

Tracking pixels helps marketers to collect user data for web, mobile & email marketing. By installing an HTML or Javascript code snippet, can track different events when the visitor acts. Marketers may use these actions to track user activities, conversion tracking, and behavioral retargeting.

When users take a certain action, such as visiting a site, opening emails, viewing your digital ad, etc. they send a request to the server to download the tracking pixel attached to the content they’re interacting with. It’s an invisible process to the user but the data collected will help marketers create better digital ad and content experiences for consumers.

A tracking pixel can collect any information about users and how they interact with your site. Some data points that can be collected include:

  • Which pages do they view
  • Operating system
  • Device information
  • Screen resolution
  • What time they visited
  • Activities during a session
  • Their IP addresses
  • and more…

How does Tracking Pixel work?

A tracking pixel is a piece of code in your site’s HTML code or email that offers an external connection to the pixel server. When anyone visits your website, their browser processes the HTML code that follows the connection and opens the hidden graphics. This action is detected and recorded in the tracking server. This approach allows various details about the visitor to be transmitted.

Tracking Pixels
Illustration by Seobility

Let’s say that we have a website such has implemented a tracking script called “pixel.js” whose code is expected to insert a tracking pixel on the page. The tracking script can access and generate requests using the data available on the page as well as setting different cookies that can be used as identifiers.

These data usually consist of data available within the HTML, within the URL, within the data layer, cookies, or accessed through an event listener or an API request. The tracking script will make different types of requests to pass that information to the tracking pixel.

Criticism of Tracking Pixels

Tracking pixels are often criticized by data privacy advocates for gathering extensive user data, often without user awareness. Since the tracking pixel cannot be seen with the naked eye and the average person does not know the significance of the small graphic even though it is visible, the tracking pixel requires the transfer of information without permission. It’s also nearly impossible to evade pixel tracking. Cookies may be removed, but the pixel communicates with new cookies any time a page is accessed.

Using pixels too often can cause your site to slow down and create a poor user experience. If your site takes too long to load, you can lose customers. Determine which pages will supply you with the best data and concentrate your efforts there first.


Tracking pixels are everywhere and for good reasons. Marketers use these tiny snippets of code to retarget advertising and measure conversions across their whole website and ad campaigns. Marketing pixels provide an unrivaled amount of data, which can help you improve your ad campaigns and gain a deeper understanding of your audience.

By that, I mean, tracking pixels maybe a teeny-tiny, practically invisible piece of technology, but they play a huge role in our current and future digital marketing landscape.

More articles coming soon…