A Microsoft AdCen­ter upgrade last week now pro­vides search mar­keters with the abil­ity to A/B test mul­ti­ple ads (Pre­vi­ously, you could run mul­ti­ple ads in Adcen­ter, but the ads would not rotate evenly, mak­ing test­ing dif­fi­cult. This even rota­tion func­tion­al­ity has been avail­able in Google Adwords for years).

Prior to this Adcen­ter upgrade, if you were run­ning mul­ti­ple ads in an ad group, Adcen­ter would deter­mine which ad to favor most of the time (i.e. – while run­ning two ads, one ad would get 93% of the traf­fic, the other ad would get 7%), and Adcen­ter would favor the ad gen­er­at­ing the high­est vol­ume of clicks (rather than con­ver­sions, which is typ­i­cally the indus­try best practice.)

As a result of this Adcen­ter fea­ture update, it’s worth review­ing some best prac­tices in A/B ad text testing:

1. Use tightly themed ad groups, so that your ads can eas­ily reflect the search query
2. Describe your offer­ing clearly, using proper gram­mar and punc­tu­a­tion
3. A/B test based on con­ver­sions, or con­ver­sion rate (rather than clicks, or CTR)
4. Test dif­fer­ent com­po­nents of an ad at a time (Head­line 1 vs. Head­line 2; dur­ing this test, make the descrip­tion lines iden­ti­cal)
5. A/B test dif­fer­ent Value Propo­si­tions (e.g. – Descrip­tion 1 in Google Adwords; or the first half of the descrip­tion line in adcen­ter)
6. A/B Test dif­fer­ent Calls-to-Actions at the end of the ad (Descrip­tion 2 in Google; the sec­ond half of the Adcen­ter descrip­tion line). Exam­ple: “F/S Ends Soon. Buy Now!“
7. A/B Test dif­fer­ent Head­lines (e.g. – Dynamic Key­word Inser­tion (DKI) vs. sta­tic ads). You may find that DKI dri­ves a higher CTR, but that may not trans­late into a bet­ter con­ver­sion rate.
8. Con­sider run­ning your tests for at least one week (or even two), because online traf­fic for many indus­tries vary each day of the week). There­fore, you wouldn’t want to com­pare traf­fic from a Mon.-Wed. period against a Thurs-Fri period.
9. Set a bench­mark period (i.e – one week with orig­i­nal ads), then launch revised ads to run the fol­low­ing 7 days (or 14 days).
10. In Adwords, punc­tu­ate the end of Descrip­tion 1, if Descrip­tion 2 is a new sen­tence. This is often over­looked, because some search mar­keters assume the descrip­tion lines are two sep­a­rate lines. But they aren’t if the ad appears in a pre­mium position.

If you have any thoughts on this list, please share your ideas in Comments.