A couple of days ago, Google introduced a new ad rotation option, for conversion optimising. Since then, I have seen it referred to as the new “conversion optimiser”, which I think causes confusion.
This new ad rotation option is in addition to the original conversion optimising option Google Adwords already offers – originally called Conversion Optimiser, but I guess now there are a couple of options they might all be grouped under “conversion optimising”.
If you are a PPC manager, you will like already be aware of Google’s original Conversion Optimiser in Adwords. It has been around for a while, and the gist of it is, that Google will use your accounts performance history, and particularly conversion history, to try and meet your cost per conversion targets. This is the actual quote from Google
It optimizes your placement in each ad auction to avoid unprofitable clicks and gets you as many profitable clicks as possible.
So, the original conversion optimisation was to improve your cost per conversion, and involved optimising your bids.
With this new optimisation, Google will show your best converting ads, more often. So, it isn’t so much about meeting certain CPA’s, but rather about increasing conversions altogether.
To have either of these conversion options work, you need to have conversion tracking set up for your Adwords, which involves putting a snippet of code on your conversion pages. Once that snippet is in place, Google will start to track your conversions, and you will be able to get all nifty metrics like conversions by keyword, adgroup and ad as well as cost per conversion and more.
After your ad has accumulated enough conversion data, Google will alert you to let you know you are eligible to participate in conversion optimisation.
For the CPA conversion optimiser, your ad rank is now going to be determined by quality score, CPA and your conversion history, rather than quality score and keyword bid. This is no magic trick, though, and Google covers themselves by saying your conversion costs may not meet your targets, and that it can be affected by changes to your website and ads. I guess it must also be affected by your keyword choice, since older keywords would have bad conversion history.
For the ad rotation optimisation, they will be automatically showing your better performing (as per conversions) ads more often. Best practice for adwords is usually to continually improve your account by making many ad versions and testing them. But to do this, you need to choose rotate evenly, and that you cannot be constantly using conversion optimiser.
Since conversion optimisation works on the historical performance of your ad, it is best to switch off optimisation when you make significant changes to your account, and keep it off until enough conversion data which is more reflective of your current account, has been accumulated.
Conversion optimising options should be used with caution. While they can be helpful, they work on retrospective information, so if there are significant changes in your website, adwords account or even your offline business or industry, you might not want to plan your future on your past performance.