When running a website, one consideration that publishers have to make to ensure a good user experience is their users’ browser choice. Few though take time to consider how a user’s choice of browser influences the ad revenue they are likely to generate. The results from our data indicate a significant variance in revenue generated by users of each of the popular web browsers. Understanding this can help publishers to target their most valuable users, whether that is through content choices or paid campaigns.
Why though should browser choice influence ad revenue? There are a number of reasons for this, but they fall into two headings: Demographic and Technical.
Demographic reasons why browser influences ad revenue
Every browser has it’s own profile of users and they are surprisingly diverse. An obvious example is that a Safari user is more likely to be the user of Apple products. Many will tell you that this makes for a more valuable user (either due to higher earnings, marketing susceptibility or both – depending on who you listen to), although our data suggests that this is not the case when it comes to ad revenue.
Other differences are less obvious. Internet Explorer users tend to be older, Chrome users are more likely to live in a city and Safari users are more likely to be female (source). There’s also pretty solid scientific evidence that browser choice is an indicator on intelligence and that users of Chrome and Firefox are likely to have higher IQs than those who favour Internet Explorer and Safari.
These differences show that each browser has it’s own user group and we shouldn’t therefore be surprised to see a variation in advertising performance across different browsers.
Technical reasons why browser influences ad revenue
The differences in revenue are not limited to audience though. Technical differences in browsers influence how ads work and how effective ad targeting through each browser is. Display ads rely heavily on cookies to convey important targeting information and browsers interfering, limiting or blocking these has a particularly significant impact on revenue. Safari, Firefox and Chrome all have their own take on how advertising cookies are handled and the impact of the more aggressive cookie blocking in some browsers is evident in our data.
How we built this data
We analysed a sample of a billion impressions served through our Ad Exchange account in the first week of June 2019. Breaking these down by each of the popular browsers serving on Smartphone, Desktop and Tablet we saw significant differences on every site. The data we have presented here is aggregated across all sites and looks at the variance from average in order to account for differences in CPMs and browser mix across different sites.
The main limitation in this method is that it is limited to Ad Exchange performance, and ignores header bidding partners. See the notes below about collaboration.
Data has been presented by device type, as CPMs are also greatly influenced by device type, which the following chart shows.
CPM by Smart Phone Browser
In our data sample, smart phone browser share was a two-horse race between Chrome and Safari. It’s no great surprise to see Chrome (owned by the world’s biggest advertising company) outperforming Safari (Owned by Apple who have taken a strategic stand against Google online advertising).
This pattern continues amongst the “also rans” with Android Browser performing at similar levels to Chrome with more privacy-centric browsers lagging behind. This data contains two surprises. The first is the gap between Opera and Safari/Firefox. This could be due to a more strict privacy enforcement in Opera, but could also be related to the way that Opera can interfere with geographic reporting. The second surprise is Microsoft’s mobile Edge browser, not just for it’s appearance, but in that it is the worst performing in this data. This is contrary to what we see on desktop, where Edge is a much stronger performer.
CPM by desktop browser
Results on desktop probably hold fewer surprises. Chrome is the most dominant and therefore tracks close to the average. Firefox and Safari are both taking a significant chunk out of publishers’ revenue as a result of their privacy-centric features, with Safari losing over a third of revenue. Microsoft’s Edge and older Internet Explorer both perform significantly ahead of Chrome. With Chrome currently placing no real barriers to ad monetization, the high performance on Microsoft browsers is likely related to the profiles and behaviors of those users.
CPM by tablet browser
The data relating to tablet use in our sample was limited (who still uses a tablet, right?), so we have limited the results to just the three most popular tablet browsers. Again, Chrome performs best for publishers, and Firefox the worst. Safari is the surprise here, performing closer to Chrome levels than Firefox.
The next most popular browser on tablet was Opera, This should be taken with a pinch of salt as there was a limited number of impressions being served to Safari on tablet in our sample. We’ve omitted it from the main charts as it only accounted for 0.5% of tablet impressions, but it is worth noting that CPMs on those impressions were a worrying -48% vs average tablet values.
Want to collaborate?
This initial study shows interesting trends in CPM rates by browser, but is across a limited number of websites. We plan to repeat the study across a larger sample of websites in the near future. If you have access to performance data in the region of millions of impressions per week and would like to help us build a more accurate picture of this please do get in touch. This can be done in a way that does not compromise any sensitive data.