Ad Blockers Are Not Created Equal: A Survey of the Shifting Landscape of Ad Block Options

Gary Portney

Analysis showing the variability of performance between leading ad blockers

In previous blog postings, I have discussed the power of permission-based advertising: by merely giving ad block users choices, without touching their ad blocker, to see or not see advertisements, has a dramatically positive impact on their behavior. At Adtoniq, we fundamentally respect and understand why people use ad blockers. But there’s a lot of different ad block software and options out there to choose from and that poses the question, “do all ad blockers offer the same capabilities and levels of protection?” They don't and here are some of the critical differences.There are two main areas where ad blockers function: search-based advertising and website advertising. In this post, I will specifically address websites and the impact ad blockers have, not just with advertising, but with other web services. To see the performance of ad blockers, we did a  small test. We loaded four of the most popular ad blockers one at a time, on a Windows laptop running Google Chrome: We chose AdBlock Plus, UBlock Origin, AdGuard and Ghostery. We then visited some popular news and lifestyle sites.

Test Results

The table below shows the cumulative number of blocked elements of content and functionality for each site by ad blocker.

  1. The test showed a wide disparity in ad blocker performance.
  2. AdBlock Plus had the highest block rate, with 100 more than the lowest AdGuard.
  3. The differences seen are mainly due to the filter lists and scripts each blocker uses and the extent to which they also block other services, not just ads.
  4. Certain ad blockers disproportionately attack specific sites. You can see with The Chicago Tribune that AdBlock Plus impacted it more than other products.

What’s Being Blocked

As mentioned earlier, it’s not just ads that are being blocked. The following illustration shows uBock Origins impact on the landing page with highlighted examples.

Included in the 43 items being blocked are Google Analytics, all the social media plug-ins including Facebook, YouTube and Pinterest and a plethora of website supporting software along with blocked ads. You will note that Google Tag Manager is also blocked. This has a snowballing impact in that Google Tag Manager is used to load a variety of other scripts, many of which have nothing to do with advertising or privacy.So many publisher tools used to measure traffic, track user activity and maintain site integrity are stopped by ad blocking, including the detection and measurement of ad blocking.

Why Ad Blockers Deliver Different Results?

All ad blockers use rules to determine what should be blocked. These rules are also known as filters, and they are provided in collections called filter lists. Ad blockers rely on a constantly evolving, volunteer community to maintain a set of filter lists to determine which services and content to block. The most popular filter lists include the EasyList and Easy-privacy list. The use of these filter lists or a combination of them determines the level of ad blocking each offer.

It should also be noted that ad blockers should more accurately be thought of as generic “blockers” because they block more than just ads; they also block analytics, social sharing widgets, optimization tools, personalization tools, forms, single-sign-on tools, and much more.

So, in general, how does ad blocking work? Here are a few examples:

  1. Ad blockers prevent browsers from loading out-of-line resources by using filter list rules that target patterns in URLs that should be blocked. These filter list rules then leverage hooks in the underlying browser to prevent the network connection from being processed. The illustration below shows the impact of filter list rules blocking social media and advertising website resources, effectively stopping them from being loaded.
  1. Often, advertising content is embedded inside other content that the end-user wants to see, which leads to the requirement that the ad blocker must be able to selectively target content within the page. Typically ID’s matching values that often indicate ads, such as “adchoices” or “leaderboard” as well looking for combinations of attributes, are screened through filter list rules. For example, many ad blockers block images that use standard IAB ad unit sizes, such as the banner ad format of 728 x 90. Identifying the content to be removed is the first step. Once identified, instead of removing the ad they generally hide elements by setting attributes including display and visibility.

In Conclusion  

The facts speak for themselves. Clearly ad blockers are not created equal and depending on which one consumers choose, the results can be vastly different.

That said, our tests reveal the real extent to which ad blockers impact advertising which results in advertisers not being able to reach a large part of their target audiences on these popular sites and at the same time the publishers are generating zero revenue.

As if this wasn’t bad enough, the fact that ad blockers render Google analytics useless means that GA is delivering inaccurate data. Then Google Tag Manager being blocked raises a whole series of problems for publishers and advertisers, including conversion tracking, site analytics, remarketing, attribution and so much more. This massively degrades the performance of sites and the apps used on them. We could continue to list all the implications, but these few examples paint a telling and troubling outcome for advertisers and publishers. Ignorance is no longer bliss. It’s time for advertisers to take action if they want to reach this unreachable audience. This can only be achieved through permission-based advertising, with advertisers and publishers working in partnership to gain consumer consent and rebuild trust with the ad blocking community.

Adtoniq Blog

See All Posts

The Power of Permission to Build Trust

Gary Portney

If you want to succeed as a brand in the current market, you need to rebuild trust. Consumers have lost faith in many of the brands that they once believed in but there is one simple tool that many companies are ignoring to rebuild that trust: permission. 

Read More

Publishers Can’t Recover What They Can’t Measure: 50% of Ad Blockers Go Undetected

Pat Whelan

It’s time for publishers to take ad blocking seriously. Most ad block detection tools used by publishers today don’t work because they are blocked by this software so most publishers don't even know the size of the challenge.

Read More

Case Study: Ad Council Campaigns See 652% Higher CTRs from Ad Block Audiences

Gary Portney

The Ad Council and Adtoniq join forces delivering COVID-19 awareness to ad block users

Read More
What is

Permission-based Advertising?

Adtoniq technology allows for ads to be served to ad block audiences with their permission which results in higher engagement and more conversions.

We only serve ads to an ad blocker when they have given some form of consent to do so. We do not force ads on ad block users, nor do we ask them to white-list or turn off their ad blockers. Users can revoke their permission at any time and we strive to make their experience fully transparent.