Joshua Edward Smith | From the blog of Nicholas C. Rossis, author of science fiction, the Pearseus epic fantasy series and children's booksI discovered alfageek’s blog fairly recently, but I’m sure glad I did. Joshua, aka alfageek, generously shares his book marketing experience with his blog’s readers. His main marketing venue is Twitter Ads (more on that in a future post), but he jumped at the chance when Bookbub offered him a chance to advertise with them.

Sadly, the experience failed to pay off. As many of you have asked me if I knew anyone who had tried it, here is a great chance to see what didn’t work for him.

The Drawbacks of CPM

From the beginning, Joshua was skeptical. He felt that CPM advertising (paying for impressions, rather than clicks) didn’t make sense since they count opening the email as an impression. Yet you have to scroll down to see the ad. That means that a lot of those “impressions” aren’t really impressions at all, so one would expect the CTR (click-through rate) to be low. In other words, not everyone would see the ad, therefore fewer people would click on it.

After running a lot of tests, it turns out his skepticism was justified. The CTR on BookBub ads is pretty consistently about 0.4%. To give you a measure of this, I have been running a series of Facebook ads for the Pearseus bundle (more on that in a future post), which consistently have a CTR around 1.5% – over 3 times that of Joshua’s.

Joshua tested this by running a Twitter ad campaign using pretty much the same creative as his Bookbub ad.

The Results

After spending $70 on BookBub, he had 128 clicks that converted to 5 sales; a CPC of $0.55. That’s 4%, which is fairly decent. Let’s put these numbers in context by comparing them to his Twitter campaign:

BookBub Twitter
CPM $2.30 $1.29
CPC $0.55 $0.12
CTR 0.40% 1.05%
Conversion 4% 3%
CPS $12.00 $4.04

(CPM: Cost for 1000 impressions; CPC: Cost per click; CTR: Click-thru-rate; Conversion: % of clickers who buy; CPS: Cost per sale.)

Even though the conversion was actually lower for Twitter, the end cost was also lower, so Twitter turned out to be 3 times cheaper. This is borne by the bottom line, which is, well, the bottom line: What each of these sales costs him. If BookBub had a killer conversion rate, it could make up for the high CPM or the low CTR. But it doesn’t.

So here is what we can conclude: Right now, BookBub ads are a poor way to sell books. I think other advertisers have figured this out because the ads I’m seeing in my BookBub emails are all for stuff other than books. And that may be the reason the book ads don’t work. The CPM for BookBub book ads should be about $0.50. But the CPM for ads in general is almost five times that high. And since BookBub is mixing book ads from their publishing partners with general ads from anybody, those general ads drive up the book ad CPMs to make them unjustifiably pricey.

In Conclusion

If anyone from BookBub happens to read this post, here’s Joshua’s advice if you want to make BookBub ads work for authors and publishers of books – advice I agree with:

  • CPC bidding, not CPM, since impressions aren’t impressions
  • Better demographic data, so we can tell who is clicking the ads
  • Throw out the random advertisers and have a pure book market

You can read the post in its entirety on alfageek or check out some beta testing tools here.