Successful Search Engine Marketing – 2. Creating Appealing Ad Text

In this second post in the ‘Successful Search Engine Marketing’ series, I’ll be providing some tips on how to make the most of the impressions your ads receive by writing compelling ad text.  Some of the recommendations in this post build on topics that were covered in the ‘Selecting and Organizing your Keywords’ article – if you haven’t done so already, check it out here. While many people will tell you that SEM is a largely scientific discipline, this is only partly true.  In order to be truly successful, you need to mix the more mathematical elements of SEM with the creative skills required in more traditional marketing channels.  Nowhere is this truer than when writing the copy for your ads.  Perfecting the delivery of your message to search engine users within a limited number of characters is an art form which can play a key role in generating qualified traffic to your website.

Most search engines have the same parameters for writing ad text, giving you a Headline of up to 25 characters, two Description lines of up to 35 characters each, and a final line for a Display URL, also with a maximum length of 35 characters.  That’s just 130 characters in total in which to get your message across to users, so you need to make the most of every word to encourage users to pick your site out of the list of advertisers returned by a search engine.

Make the Ad Text relevant and compelling

The first thing to make sure is that you are highlighting a unique selling point about your site in order to differentiate yourself from the competition and give users a reason to click on your ad.  Set users’ expectations by letting them know what they will see when they land on your website.  If the main selling point of your site is that offers CD reviews from thousands of users across millions of products, make that clear in your ad text.  This can help to improve not only the Click Through Rate (CTR) of your ads, but also the conversion rate of clicking on the ad to making a purchase on eBay.  Most of the time the more specific and targeted you can make your ad text the better. 

Last year eBay tested inserting the number of available listings for a specific product that matched purchased keywords into our SEM ads.  For example, a user searching for the video game ‘Call of Duty 4’ may have seen an eBay ad saying ‘948 items available’.  Compared to the best performing ad text we were running at the time, we found that including this information in the ad increased the CTR by 20% and the conversion from click to purchase by 10%.

Dynamic Keyword Insertion

You should also make sure that your ad is as targeted to what the user is looking for as possible.  One way to do this is by using ‘Dynamic Keyword Insertion’ to automatically insert the keyword purchased into your ad text.  This has two advantages when it comes to attracting a user’s attention: firstly, it gives the user an indication that your ad is relevant to what they were looking for; and secondly, any words in your ad text which match those used in the user’s query will appear in your ad in bold, standing out from the rest of the page.  In our experience, Dynamic Keyword Insertion works best when used in the Headline of your ad, as users tend to read this line first and so improvements to the ad text of your Headline usually have a bigger impact on your CTR than changes to the rest of your ad.  In addition, using Dynamic Keyword Insertion in your Display URL can be extremely effective, as it gives the user confidence that they will be taken to a page on your website that is relevant for the product they are searching for – though if you do this, you should make sure that this expectation of an appropriate landing page is met!  Dynamic Keyword Insertion is often most effective if used for ads purchased on Exact Match, since the keyword inserted into the ad matches perfectly the word(s) a user has typed into the search engine.  However, if used well Dynamic Keyword Insertion can still lead to a significant improvement in your CTR on Broad and Phrase match types.

In order to use Dynamic Keyword Insertion, you need to place the word ‘KeyWord’ inside curly brackets, followed by a colon and some alternative default text to be used in case the keyword purchased is too long to be inserted into the ad.  For example, if your website contains CD reviews and the keywords in your Ad Group are all the names of rock bands, you might submit an ad to a search engine with the Headline ‘Reviews of {KeyWord: rock} CDs’.  When a user search triggers your ad for the keyword ‘Green Day’, the user would see your ad with the Headline ‘Reviews of Green Day CDs’.  If the search was for a band with a longer name, such as Queens of the Stone Age, the alternative default text would be used and the Headline of your ad would read ‘Reviews of rock CDs’.  Given the developing trend towards searchers using longer keyword phrases, it is worth taking the time to optimize the default text you use with Dynamic Keyword Insertion, as users are now increasingly likely to see this part of your ad text.


As with all other aspects of Search Engine Marketing, one of the most important things to remember is when creating appealing ad text is that you should be constantly testing and optimizing your ads.  In order to enable this, most search engines give you the option of having more than one ad in each ad group.  They will also rotate between your different ad combinations, giving them each a percentage of the total impressions for that Ad Group, in order to allow you to test which ad performs best.  In comparison to manually taking one ad out and putting a new ad in, this rotation of ads is extremely useful as it allows you to run true A-B tests of your ads, without having to control for external factors such as seasonality.  Given the numerous different variables to play with when creating ad text across four different lines of text, using this ability to rotate ads in a smart way is critical.

When you have multiple ads in the same Ad Group, there are two different settings you can use to rotate your ads.  The default setting for most search engines is to have the ‘Optimize’ option turned on.  This will rotate your ads, but insert the ads in that Ad Group which have the highest CTR into the auction to be shown against a user query more often than your ads with a lower CTR.  This has a number of advantages: firstly, since ads with a higher CTR are likely to attain a better position in the auction, you should receive a higher number of impressions as ads with lower CTRs may not appear on the first page of results; secondly, these impressions are more likely to result in clicks since these ads have a higher CTR; and thirdly, having ads with a higher CTR served more often should increase your Quality Score, thereby lowering the minimum CPC you need to pay in order to appear against certain keywords.

However, utilizing the ‘Optimize’ option for your ads is not always the right approach.  If you are A-B testing multiple ads, ideally you want to get an answer as to which ad is the best as quickly as possible, so that you can remove worse-performing ads from your Ad Group, leaving only the best performing (and allowing you to move on to your next test).  In order to do this, you need to be sure that the differences in ad performance are statistically significant enough to be able to say with a high degree of confidence that one ad’s performance is better than another’s because of the different ad text rather than any other random factor.  While there are complex formulae you can use to work out whether you have enough data to conclude that a difference in ad performance is statistically significant or not, ensuring that each ad has received at least 1,000 clicks is usually a good rule of thumb.  Using the ‘Optimize’ function to ensure that your best performing ads are shown more often means that it takes much longer for all of your ads to receive 1,000 clicks than would be the case if you turned this function off and rotated impressions evenly across your ads.

One other reason that using the ‘Optimize’ function is not always the best option is that CTR may not be the correct metric for which to optimize your ads.  While CTR gives a good indication of whether your ad is attractive to users, the clicks you are getting to your site from high CTR ads may not be very targeted.  For example, if you are a CD reviews site but use the Headline ‘Free iPods – click here’, you may well receive a large number of clicks, but those users will be disappointed when they actually reach your site.  Ideally you should try to track conversions from each ad variation separately, so that you can optimize according to the number of Purchases per Impression rather than CTR.  One real-life example here: a few years ago eBay tested using Dynamic Keyword Insertion in three of the four lines of ad text.  When analyzed on CTR, this ad outperformed all of our others by more than 20%.  However, when we looked at Revenue per Impression, an ad which included a message about finding great deals on eBay in Description Line 1 beat it by more than 20%, as the clicks generated were more targeted and converted better into purchases.  While optimizing ads according to Revenue per Impression takes more work than optimizing on CTR, it can be well worth the extra effort.   One way to do this would be to use a unique identifier in the destination URL of each search engine ad.  Then when traffic generated by this ad clicks on an eBay link, pass this same unique identifier through in the custom id field of the eBay Partner Network tracking link.  Then use the transaction download report to run analysis - see the advanced analysis section of this previous blog post for details on how to do this.

Stay tuned for my next blog post, in which I’ll give you some more tips on how to make those clicks pay even more by improving your landing page optimization. 

Chris Howard

European eBay Partner Network team leader and one time eBay UK SEM manager