I probably post a guest post here on average once a year and I really wasn't in the mood to cover how Google Chrome ad blocking works in detail. I saw Glenn Gabe posting tons of examples on his Twitter account, so I asked him if he wants to do a post here and he agreed. You can learn more about Glenn Gabe over here.
In June of 2017, Google announced that Chrome would start filtering ads on sites that provide intrusive advertising. And in December of 2017, we even received a date from Google, which was February 15, 2018. It was a welcome announcement as aggressive advertising has become a huge problem across the web. From popups to interstitials to autoplay video with sound to pages inundated with ads, browsing the web has become video game-like. For example, how quickly could users shut off the sound of annoying ads, dodge popups, avoid interstitials, and more as they browse the web. It's annoying and disruptive (and could even be deceptive).
Threshold and formats
So how does Chrome determine if a site should have ads filtered or blocked? That's where the Coalition for Better Ads comes in, where Google is a prominent member. Based on research, the coalition determined a number of formats across desktop and mobile that users deem intrusive. You can see the formats below. They include pop-up ads, autoplay video ads with sound, prestitial ads on mobile, ad density higher than 30% on mobile, etc.
From a threshold standpoint, if 7.5% of all pageviews checked violate the better ads standards in the first two months of the program, then a site will be in violation. Then 5% in the following four months, and then 2.5% after that.
Examples of ad blocking, I mean filtering. What it looks like in action:
Since the June 2017 announcement, I've been collecting a list of sites that are in violation (across both desktop and mobile). That list has grown quite large and contains a range of sites globally. My goal was to test a number of those sites once 2/15/18 arrived to see what ad filtering looked like in the wild.
Well, 2/15 arrived and the stable version of Chrome was NOT filtering ads. Google did say they would roll ad filtering out gradually over time, so this wasn't a huge surprise. I did notice you could see ad filtering in action in Chrome Canary, a version of Chrome containing the newest features that are being tested. Based on seeing ad filtering in action, I wrote a post explaining what I was seeing, which included a number of examples of ad blocking in action.
But again, that was just Chrome Canary. I eagerly awaited the stable version of Chrome to begin blocking ads. That's when things would get really interestingâ¦ since sites would have ALL ads blocked on the site. And it wasn't too long before that happened.
2/27/18 - Ad filtering comes to the stable release of Chrome
On February 27, 2018 I noticed the first examples of ads being blocked in the stable version of Chrome. I saw this on desktop first, and then finally on mobile the following morning (in Chrome for Android).
Again, if a site is in violation, all ads are blocked on the site. A notification appears in the browser window explaining that ads are blocked. If you click that notification, you are presented with a message about intrusive ads, with the ability to include ads from the site (if you want). I have no idea why anyone would do that, but the option is there. You can also access site settings in Chrome to view more about the site, which also includes information about ads being blocked. You can see examples below.
Examples of Chrome ad blocking in action:
1. Chrome ad filtering on desktop. The site is NOT in violation on mobile.
2. Another example of ad filtering on desktop.
3. Chrome ad filtering on mobile. Notice the notification at the bottom of the viewport.
4. Another example of ad filtering on mobile.
Nuances And Observations With Ad Filtering In Chrome
Preroll video ads with sound: The format that was conveniently left out...
When digging into sites that were in violation, I noticed that preroll video ads with sound were NOT a violation. That struck me as odd. So autoplay video with sound is a violation, yet preroll autoplay video with sound was not a violation. Sounds strange, right?
Well, it's estimated that YouTube generates up to $15 billion in revenue per year and guess which format drives a lot of those ads? You got it. Preroll video ads with sound. It seems the format never made its way into the survey run by the Coalition for Better Ads to gauge which formats were intrusive. And again, Google is a prominent member of the coalition. It's just an interesting side note.
Desktop and mobile handled separately.
It's important to note that desktop and mobile are handled separately from an ad blocking standpoint. So a site can be in violation on desktop, but not on mobile (or vice versa). There are a number of sites on my list that fit into this category.
Notification only shows on initial load.
I noticed that the notification in the mobile version of Chrome only displays on initial load. And that's the only op to turn ads on for those that wan to do that. That's unless a user knows how to go in and change that in the Chrome settings. The desktop version of Chrome seems to keep the notification in the browser window even after revisiting the site or loading new pages.
The Ad Blocking Impact, and Moving Forward
Google has said that ad filtering impacts a small percentage of sites. That might be true, but I have a large list of sites being impacted right now. And those sites are having ALL ads blocked. For those sites relying on advertising to survive, ad filtering by Chrome is a killer.
Of course, the solution is pretty easy. Just remove the intrusive ads and request a review in Google Search Console (in the Ad Experience report). During my analysis of sites in violation, I have come across a number of them that have fixed their intrusive ad situation. When checking the sites in Chrome, ads are not being filtered now (when they were just last week while testing in Chrome Canary).
My guess is many sites will start making changes now that the stable version of Chrome is filtering ads. The impact to their ad revenue will be overwhelming. For example, remember the site above with the giant area of white space where ads should run? I'm sure that's shocking to the site ownerâ¦ and I'm sure that will lead to the removal of intrusive ads.
One thing is for sure, I'll keep analyzing sites on my list to see how things go. I'll post updates on Twitter and on my blog detailing what I'm seeing. Make sure you have checked your site via the Ad Experience report in GSC (and manually via the stable release of Chrome). Don't get blindsided by ad filtering. Good luck.
Forum discussion at Twitter.