Starting Fresh: Rethinking PPC Ad Copy Testing Pt. 2

In one of our previous articles, we discussed two approaches to ad copy testing; impression split testing and optimize for conversion rotation testing.

To summarize, impression split testing is done to deliver the same number of impressions to each ad in the test. This is done to allow each ad to have an even opportunity to show and the winner would be decided based on KPIs important to the business. Optimize for conversion testing leverages Google Ads’ (formally Google AdWords) algorithm to deliver the best ad copy based on several specific signals (i.e. user location, device, time of day, etc.). Instead of trying to figure out which ad is the best, this setting is designed to have all ads in an ad group work together and allow the system to show the ad that is best for each query.

Historically the impression split testing has been our preferred approach to ad testing. However, we have since tested the new optimize setting to see how effective it could be. This article provided an interesting way to test the results of this setting, which we included an excerpt below to help describe the test:

“Test an ad group with one ad (A) against an experiment ad group with four ads (A, B, C, and D) with rotation set to optimized. You can use drafts and experiments to create these two versions. That way, you’re testing to see whether or not more ads result in more impressions and clicks at the ad group level.”

Results & Insights:

If you refer to the results below, you’ll find performance for the ‘test campaign’ (leveraging the ‘optimize’ setting with 4 ad variations) against the ‘control campaign’ (only running 1 ad variation). As you’ll notice, there wasn’t a significant difference between the two data sets.

We found that the test campaign was able to achieve better CPCs and higher impression volume, but the control campaign had a better conversion rate and CPA. These results gave us confidence that this new ad setting wouldn’t hurt campaign performance, but also may not make it significantly better either.


Since we didn’t notice much of an impact on performance, we wouldn’t recommend completely overhauling your approach to ad testing. We found that a secondary benefit to using the ‘optimize’ setting is that we can let ad copy tests run longer, because Google will in most cases match the strongest ad to the most impressions. You might find it worthwhile to run a similar test for your account, to see if your results are similar.

If you were interested in learning more about you should rethink PPC ad copy testing, please contact us by email at  or by phone at 781-591-0752.