What we tested
The test results
We tested ten different ad blockers and the results were that only the ad blockers color coded green were correctly identified by PageFair, while the red blockers either completely hid from PageFair running undetected, or were incorrectly attributed as nonblocked when they should have shown as blocked. These are the blockers we tested:
- Adblock Browser for Android
- AdBlock Plus
- AdBlock Plus Content Blocker for iOS
- Brave Browser
- Opera desktop with built-in blocker
- Opera Mini with built-in blocker
- uBlock Origin
- UC Browser
We tested AdBlock version 3.1.1, using the default settings, running on Chrome. PageFair successfully detected this ad blocker. However, after going to the AdBlock options and checking the box for the Easy Privacy list, PageFair completely failed to detect these page views at all. The reason for the complete failure here is that pagefair.com appears on the Easy Privacy filter list, and so consequently their analytics script gets blocked from loading. If you try embedding the script inline to avoid that problem, when it attempts to send anayltics out it will get blocked then. Publishers will not see these blocked page views at all.
Adblock Browser for Android
We tested Adblock Browser for Android version 1.1.1, using the default settings. PageFair successfully detected this.
We tested AdBlock Plus version 1.12.2, using the default settings, running on Chrome. PageFair successfully detected this.
AdBlock Plus Content Blocker for iOS
We tested AdBlock Plus content blocker for iOS. PageFair incorrectly attributed blocked page views as unblocked page views. Publishers will incorrectly view iPhone and iPad users who are using the AdBlock Plus content blocker as non-blocked users.
We tested the Brave browser version 0.12.0, using the default settings. PageFair failed to detect Brave and incorrectly attributed these page views as not blocked, even though they should have shown as blocked. That is, publishers will incorrectly see their Brave users as non-blocked.
We tested the Ghostery blocker version 126.96.36.199 on both Chrome, FireFox, and IE, as well as their dedicated Ghostery browser, using the default settings. PageFair failed to detect Ghostery and incorrectly attributed these page views as not blocked, even though they should have shown as blocked. That is, publishers will incorrectly see their Ghostery users as non-blocked.
Opera Desktop with built-in blocker
We tested the desktop Opera browser version 188.8.131.52 with built in ad blocking, using the default settings. PageFair failed to detect Brave and incorrectly attributed these page views as not blocked, even though they should have shown as blocked. That is, publishers will incorrectly see their Ghostery users as non-blocked.
Opera Mini with built-in blocker
We tested the mobile Opera Mini browser version 18.0.2254.106542 with built in ad blocking, using the default settings. Like it’s desktop twin, PageFair failed to detect Opera Mini and incorrectly attributed these page views as not blocked, even though they should have shown as blocked. That is, publishers will incorrectly see their Opera Mini users as non-blocked.
We tested uBlock Origin v1.9.4. Because this ad blocker comes with the EasyPrivacy list enabled by default, PageFair does not even detect a page view for uBlock users.
We tested UC Browser version 184.108.40.2060, using the default settings. PageFair does not even detect a page view for uBlock users, so you don’t even know your UC Browsers were on your website, according to PageFair.
See the PageFair script fail for yourself
To see the PageFair script fail for yourself, follow these steps:
- If you are on desktop or laptop, add the EasyPrivacy list to your ad blocker by clicking on the link in this step. If you are using AdBlock (as opposed to AdBlock Plus) or if you are using uBlock, simply make sure the checkbox for EasyPrivacy (may also be called Privacy) is enabled on your options page.
- Visit PageFair’s website.
- Open your browser console. You can right-click/Inspect or hit F12, among other ways to do this.
Google Analytics is also blocked by some blockers
As can be seen in the console snapshot above, Google Analytics is also blocked by some ad blockers. If a publisher is relying on an ad block detection script that sends its results to Google Analytics or similar systems, the publisher will be missing data to the extent that blockers block Google Analytics.
Ultimately, our research points to a rather frightening trend – publishers are being lulled into a false sense of security. They are relying upon technologies that do not accurately detect ad-blocking, and these inaccuracies are invisible to those who have implemented strategies to counter ad-blocking. This will become increasingly problematic as ad-blocking continues to expand dramatically on mobile and becomes increasingly sophisticated on desktop. Publishers need to be aware of these shortcomings, as the business implications are profound.
PageFair incorrectly attributes Brave users as nonblocked, incorrectly attributes AdBlock Plus for iOS users as nonblocked, and fails to see at all any user subscribing to the Easy Privacy filter list. By default, uBlock comes with the EasyPrivacy list enabled, PageFair will never record impressions from uBlock users.
We do not yet know the size of this inaccuracy, and we are investigating ways to measure how large this inaccuracy is. In the meantime, one thing we can conclude is that a publisher’s actual ad block rate is higher than what they see in PageFair.