The Tracker Tax

Ghostery study reveals that tracking makes websites load 2 times slower

Simply cut your page load times in half by blocking trackers and eliminating clutter

Tracking scripts from Google, Facebook and many other companies monitor every move you make on the web to build a profile about you. And they make you pay for this invasion of your privacy: each tracker on a webpage costs you half a second. Using a tracker-blocking technology like Ghostery saves you time and protects your personal data.

The prevalence of trackers

According to a recent study by Ghostery, trackers – pieces of code that collect personal information and monitor users’ online behaviors – are present on a majority of websites. Of the 500 domains analyzed in this study, nearly 90% of page loads had at least one tracker on them and over 20% had 50 or more trackers. Only 10% of page loads were tracker free.

Study Overview

The study titled “The Tracker Tax: the impact of third-party trackers on website speed in the United States”, looks specifically at how the presence of these trackers affects page performance. It seeks to determine whether there is a relationship between the number of trackers on a web page and the time it takes to load that page. The answer is a very clear YES.

Using a custom-built web crawler to collect internet data, the study assessed the number of trackers on and the page load times of the top 500 websites in the United States, as determined by Alexa. Since the goal of the study was to measure the effects of trackers on page load times for the average internet user, it focused on the most popular American websites. The crawler was run under two configurations: 1) with no trackers blocked, and 2) with the Ghostery browser extension blocking all trackers.

The findings of this study are particularly relevant today, in light of the recent repeal of net neutrality in the United States and the likely circumstance that Internet service providers (ISPs) will begin to separate internet traffic into slow and fast lanes. In such a world, knowing what other factors impede website speed and cause longer page loads becomes invaluable for improving your online experience.

The adverse effects of trackers

When you visit a website containing trackers, the tracking operator – Google and Facebook being two of the most prominent – can monitor your actions and develop a profile that contains unique personal data about you.

Trackers can gather a variety of information about you such as your political views, interests, shopping behaviors, and even more sensitive information about your health and sexual orientation. Trackers are constantly gathering personal data, and unfortunately, most people are not aware that this behind-the-scenes activity is happening.

A previous Ghostery study titled “Tracking the Trackers: Analysing the global tracking landscape with GhostRank”, explored how tracking threatens users’ privacy online. This latest study builds on that research and focuses specifically on how the presence of trackers adversely affects website performance. It reveals a clear-cut relationship between the number of trackers on a page and the time it takes for the page to load.

The Tracker Tax

The measurable impact of tracker volume on page load times is what the study calls the tracker tax. Think of this “tax” as the additional time that trackers demand from you as you browse a page. If we consider the age-old adage – time is money – then this tax has monetary implications.

Without blocking trackers, only 17% of all the pages in the study loaded within 5 seconds. All other pages loaded much more slowly: it took more than 10 seconds to load nearly 60% of the pages, more than 30 seconds for 18% of the pages, and nearly 5% of the pages took over a minute to load.

The study also shows that on average, websites take more than twice as long to load when trackers are not blocked (19.3 seconds), compared to when the Ghostery browser extension is used to block all trackers (8.6 seconds). This means you spend an extra 10 seconds per load weighed down by trackers – which can add up quickly given how many different pages we visit online.

The cumulative effect of trackers

So, does it matter if a web page has 1 tracker, 10 trackers, or 100 trackers? The answer is yes.

As outlined in the study, there are several models for quantifying the tracker tax, the simplest suggesting that on average, each additional tracker adds half a second to a page load. Other models evaluated in the study imply compounding effects on page load times, indicating that as the tracker count grows, each additional tracker has an increasingly larger impact on page load times.

When looking at the 10 slowest sites in the study’s sample, the time saved using Ghostery’s tracker blocking technology is particularly interesting. When all trackers were blocked on the 10 slowest domains, load times on average were 10 times faster, saving the user an average of 84 seconds per page load. In the most extreme example, it took on average 126.5 seconds to load with trackers unblocked and only 13.3 seconds with trackers blocked.

The study also revealed that trackers attract more trackers, a phenomenon known as piggybacking. This is when one tracker placed directly on a website gives access to other “piggybacking” trackers that were not originally on the site, which raises several concerns.

Some of these piggybacked trackers include data companies that sell the data they gather to other businesses looking to target people. These trackers are not placed directly on the website, so the site owner doesn’t necessarily know who is collecting data about their users. In other words, the site owner may be complicit in third-party data sharing unknowingly or without their consent. This is obviously a privacy concern, on top of a likely hefty tracker tax caused by allowing trackers in bulk.

How to protect yourself from trackers

Simply put, tracker blocking technologies save you time. On average, websites take twice as long to load without trackers blocked. This wasted time adds up quite quickly as many pages have upwards of 50 trackers present. There are clear subjective dollar costs of the unproductive time expended while simply waiting for trackers to load on a page.

Not only do tracker-blocking tools speed up your browsing, they also help stop third-party data sharing by blocking piggybacked trackers. Without a tracker blocker, a snowball effect can occur, where trackers bring in more trackers that can then bring in more trackers, and so on. Blocking trackers restricts this chain effect from occurring, which saves you time and protects your personal data.

The companies behind online trackers don’t want users to think about what is going on under the radar. In fact, “being tracked” by trackers is akin to a silent tax levied on users: the major tech giants along with lesser known companies are making you pay with your data each time you visit a website.

Essentially, you’re paying to be spied on: the fees you pay to your ISP to access the internet, the time you spend visiting your favorite websites and giving up your personal information to trackers, and the time you lose each time a tracker slows down your browsing are just the “costs of doing business”. The problem is, these costs are very steep when you consider what the user gives away in these transactions, and many are unaware this transaction is even happening.

Fortunately, there are steps you can take to protect your privacy online and save time waiting for websites to load. Tracker-blocking technologies like Ghostery work to speed up page loads and block trackers from accessing your personal information. Ghostery combines its tracker blocklist with AI-powered Enhanced Anti-Tracking to anonymize your data, while its Enhanced Ad Blocking feature blocks ads to clean up your web browsing experience. Ghostery provides a cleaner, faster, and safer browsing experience for all.


The study is based on data generated using a custom-built web crawler to collect the number of trackers and page load times for the top 500 websites in the United States, as determined by Alexa. The crawler was built with Selenium running Chrome on the desktop environment, making GET requests from a server based in New York City. For each website, the crawler used the Ghostery browser extension to collect the count of third-party trackers detected and the seconds to load that page.