Ad delivery settings are very important when it comes to split testing ad copy.

Here’s how you can change your ad delivery settings:

Click on a campaign -> Settings -> Ad Delivery: Ad rotation, frequency capping

There are four different options:

“Optimize for clicks”: Adwords will show ads with the highest click through most often.

“Optimize for conversions”: If you are rotating different ad creative, Adwords will then show the best converting ads more often.

“Rotate evenly”: Adwords will rotate your ads evenly for 90 days and then show the ones with the highest click through rate most often.

“Rotate indefinitely”: Adwords will rotate your ads evenly indefinitely.

If you are split testing ad copy, you should always use the setting “Rotate indefinitely” in order to ensure that each ad variation receive the same amount of impressions.

However, if you are running multiple ad variations and you are not actively monitoring and updating the ads based on performance, your best option is “Optimize for conversions”. This will ensure that low performing ad variations receive fewer ad impressions and clicks.