Amazon CPM versus Adsense Ads

Been testing Amazon CPM ads on a couple sites lately to see how they perform. So far, my main test was to place it in a lower quality position on a site that has a techie audience, so the visitors typically have very low click rates on adsense ads. The cpm rate for the one ad has settles in at over $1, which actually compares favorably with adsense and may even beat it for this one spot. The next step is to try replacing the remaining adsense ads on this site and see if my overall earnings increase or not. But I’m being hampered by Amazon shortcoming #1:

-Con: Amazon CPM ads do not offer a responsive ad unit option

The current site has responsive ads, so the page can resize and they will resize with it. Amazon only offers the standard sizes like 728×90, 160×600, 350×200 etc. These are great, but I can’t just swap out the responsive ads with them, so I’d have to add some coding to determine if the user is mobile and skip the amazon ads in these instances. This is too much effort at the point so I haven’t gotten around to doing it. (Maybe this could be a future service offering?)

A few other observed Pro’s and Cons:

-Pro (or Con?) – Amazon is CPM based only, and requires you place backup ad code and set a CPM floor for the ads.

This is considered a more advanced option for many users, so it makes implementation a bit more of a headache. You can set up an adsense ad to fill in for the cpm one if it doesnt have anything to show, but this will be driven by the floor cpm you set- go too high, and nothing will show- too low, and you’ll likely loose out on revenue. So, it becomes something you have to watch and fiddle with a bit to optimize, instead of the set-it-and-forget-it way that adsense typically works.

-Con- Amazon Javascript is not async?

I haven’t fully checked this out, but the code script provided by amazon cpm ads appears to not be asyncronous. This could potentially cause your site to load slower than before. Async is almost a basic requirement for sites nowdays, so it’s strange that Amazon would do things this way.

-Con- Reporting – Amazon  reporting for the cpm ads is pretty basic

Overall, it feels like this ad offering was rushed out and perhaps amazon will continue to improve upon it over time. Even the other affiliate ad offerings from amazon are pretty polished nowdays, so the cpm one is lagging even against other amazon offerings.

But in the end, the main thing we care about is- will Amazon make more revenue for you than Adsense? My initial testing looks like it’s a good way to make some extra revenue off your website without diminishing your adsense revenue dramatically- so, the answer is “Yes, sorta”. It may even outperform Adsense on sites that get a lot of traffic but the visitors tend to not click ads, since Amazon is CPM based and not as concerned about actual clicks. But overall, (sigh), at least for now, Adsense still seems to be king.