Isaac Newton’s Third Law of Motion tells us that “for every action there is an equal and opposite reaction.” This is also true in advertising. SEM provides the perfect laboratory to test and learn how customers will react to different calls-to-action.

The industry standard best practice is to include a call-to-action in every piece of advertising copy. But thanks to Boost Media’s expert team of data scientists, we now have insight into which calls-to-action perform best in retail SEM ads. In honor of Newton’s mathematics background, we share our findings in the form of a cryptogram.

Solve the cryptogram to find out which call-to-action improves conversions-per-impression by 59%

SEM advertising call-to-action cryptogram.

Cryptogram which holds to key to what is the best call-to-action in retail SEM advertising.

*CPI refers to conversions-per-impression, a metric which takes both CTR and conversion rate into account.


  1. This data indicates that customers respond to copy that is about the customer, not the advertiser. Tell customers what they can get. Don’t just tell them to buy what you have to offer. There is a subtle difference between these two interchangeable calls-to-action: one is focused more directly on the customer.
  2. All branding and advertising copy needs a strong call-to-action. You can use SEM creative testing to learn what works best for your brand and your nuanced audience leveraging those findings across marketing channels.

Tune in next Tuesday for more CMO insights plus retail SEM ad copy benchmarks.

Click here to see our methodology.

Featured image credits to


About Boost Media

Boost Media increases advertiser profitability by using a combination of humans and a proprietary software platform to drive increased ad relevance at scale. The Boost marketplace comprises over 1,000 expert copywriters and image optimizers who compete to provide a diverse array of perspectives. Boost’s proprietary software identifies opportunities for creative optimization and drives performance using a combination of workflow tools and algorithms. Headquartered in San Francisco, the Boost Media optimization platform provides fresh, performance-driven creative in 12 localized languages worldwide.