Online advertising materials have become increasingly complex and resource-heavy, significantly degrading user experience when visiting websites. Google Chrome proposed a solution — blocking "heavy" ads, announced in 2020 (at the time, heavy ads constituted less than 0.3%) and implemented in Chrome 85 in August of the same year. This article explores the concept of heavy ads, why Chrome is fighting against them, and the impact of this initiative on the advertising market.

What are heavy ads?

"Heavy" ads are advertisements that:

• Consume excessive device computational resources;
• Utilize a significant amount of network traffic;
• Negatively affect page performance and user experience.

Google defines heavy ads based on the following thresholds:

• Consumption of more than 4 MB of network traffic;
• CPU usage exceeding 15 seconds over any 30-second period;
• Cumulative CPU usage exceeding 60 seconds.

Ads that exceed these thresholds are automatically blocked by the browser.

Blocking mechanism

The mechanism for blocking heavy ads in Google Chrome is based on intervention technology. The browser analyzes loaded resources and measures their consumption. If the specified thresholds are exceeded, users see the message: Ad removed. It is important to note that this feature works across all Chromium-based browsers, including Microsoft Edge.

Although users can manually disable this feature, it is rarely done in practice.

Why did Google target heavy ads?

Google's primary motivation is improving user experience. Research shows that ads overloading devices or slowing down pages annoy users and reduce trust in publishers. This is especially critical for the growing mobile audience, where resource-intensive ads significantly reduce battery life and increase mobile internet costs.

Moreover, this move benefits Google in terms of positioning. Implementing such measures reinforced Chrome's reputation as a performance- and user-focused browser. Simultaneously, Google gained additional user data through this positioning.

As one of the world's largest advertising platforms, Google used heavy ad blocking as a tool to filter out less effective competitors unable to adapt to new standards. Google seeks to control advertising standards, forcing the market to follow its rules. Companies unprepared to meet these restrictions must invest significantly in optimizing technologies, reducing their competitiveness and strengthening Google's market position.

Impact on the Advertising Industry

The initiative to block heavy ads has elicited mixed reactions within the industry. On one hand, it motivates ad developers and platforms to optimize content by reducing its weight and avoiding excessive animations and JavaScript. On the other hand, such adaptation requires significant resources and investments, complicating market competition.

Google's advertising platform, as expected, was the most prepared for these changes. Smaller players faced difficulties due to a lack of resources for necessary adaptation.

Technical Aspects

Blocking heavy ads relies on three key technologies:

• Sandboxing: Chrome isolates ad elements within separate frames (iframes). This ensures each ad's independence from the rest of the page content and prevents ads from affecting overall site performance. This isolation allows the browser to safely stop heavy ads without disrupting other elements. Additionally, the sandbox protects the device from potentially malicious code in ads.
• Performance API: This technology measures resource consumption by each ad. It monitors loading time, CPU usage, and data bandwidth consumption. Ads exceeding set limits are automatically blocked, improving site performance, reducing delays, and conserving user resources such as battery life and mobile data.
• Interventions Framework: This mechanism enables the browser to control ads consuming excessive resources. If an ad exceeds CPU usage limits of 15 seconds over a 30-second interval or downloads more than 4 MB of data, Chrome automatically stops it. This approach protects user experience and device performance. The framework is regularly updated to adapt to new threats and challenges.

How does this affect publishers?

Website owners now have an additional parameter to monitor in their advertisements. However, if a publisher already maintained high-quality ads, no new actions are required on their part.

It is important to note that heavy ads are not monetized. To diagnose such ads, follow these steps:

• On the client side, in the browser:
  • Identify the ad block containing heavy ads;
  • Analyze the auction for the specific banner space;
  • Determine the auction winner;
  • Review and save the winner's response using DevTools to identify the specific creative.
• As a result, you will be able to identify the ad network and the specific creative flagged as heavy.

Google's initiative to block heavy ads has positively impacted user experience, as such ads caused inconvenience for everyone. Publishers only need to continue monitoring their website's ads and tracking poor-quality or malicious content. Overall, this initiative has proven successful.