Ghostery Study Reveals Trackers Make Websites Load Twice as Slow

Third-party trackers cost users an average of 10 extra seconds per page load time; internet users can double their browsing speed by simply blocking tracking scripts

New York, NY – May 1, 2018 – A new study published today by Ghostery, a free browser extension that makes your web browsing experience cleaner, faster and safer, and its parent company Cliqz, reveals that in addition to alarming privacy implications, today’s widespread practice of tracking every single user’s online behavior has a huge impact on web performance. Looking at the top 500 websites in the United States as determined by Alexa, the 2018 Tracker Tax Report measured the impact of trackers on website performance for the typical internet user. The study found that on average, trackers make websites load twice as slow compared to when trackers are blocked. With 90 percent of page loads containing third-party trackers, there’s a clear correlation that’s costing users time.

Third-party scripts cost you an average of 10 seconds each time you load a webpage

Third-party trackers on websites – like Google, Facebook, Comscore and Twitter trackers, among others – are constantly scraping personal information, from political views to shopping habits to health and sexual orientation. What many consumers don’t realize is that in addition to privacy implications, trackers adversely affect website performance, something called the “tracker tax,” the measurable impact of tracker volume on page load times. The study found that each tracker on a webpage costs you a half-second. Websites can have over a hundred trackers, which adds up to minutes of productivity lost. By blocking third-party scripts, users can avoid this “tax” and save an average of 10 seconds per page load, while doubling their browsing speed.

“Tech companies, big and small, will never curtail their data collection practices,” said Jeremy Tillman, Director of Product at Ghostery. “Most have a business model that incentivizes them to harvest huge amounts of personal information, resulting in not only a breach of user privacy, but also unintended consequences such as dramatically slower websites. That’s where the role of consumer empowerment comes into play. Users need to proactively fight back against this attack on their browsing experience by using privacy tools and ad blockers as weapons to block trackers, reduce clutter and double website speeds.”

Additional highlights from Ghostery’s 2018 Tracker Tax Report include:

  • Pervasiveness of Data Trackers: Nearly 90 percent of page loads had at least one tracker, 65 percent had at least 10 trackers and about 20 percent had 50 or more trackers. Only a mere 10 percent were tracker free.
  • When the Tracker Count Grows, Load Time Slows: On average, websites that contained active trackers took twice as long to load (19 seconds) compared to websites with trackers blocked by Ghostery (8.6 seconds). Additionally, it took more than 10 seconds to load nearly 60 percent of webpages with trackers and 5 percent took over one minute to load.
  • Time Saved with Trackers Blocked: The 10 slowest sites examined took an average of 127 seconds to load with trackers present, but when Ghostery blocked the trackers, the average load times were 10 times faster, saving users 84 seconds per page load.
  • The Piggybacking Problem: Trackers can attract more trackers in a phenomenon known as “piggybacking.” This is when a single tracker gives access to another tracker that was not originally on the site. Piggybacked trackers include data aggregators that sell the data they collect to other organizations, which can result in a lack of control over third-party tracking for website owners.

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The study was conducted by Ghostery and its parent company Cliqz and 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.

Contact Information
Diffusion PR for Ghostery
Jenna Saper