Today, we’re happy to announce the launch of 434,216 new ad unit sizes! Or in other words, we’ve just made it possible to create custom ad sizes to give you more flexibility and enable you to better design your content for your users.
Custom sized ads behave just like their standard size counterparts, showing a text or display ad depending on which is likely to have the best performance for the impression.
For text ads, we’ll determine the optimal number of text ads to display for a given impression, and show the ads the same way they appear inside standard sizes. Our system predicts the value of each competing ad for every impression, based on historic performance and comparison across a variety of scenarios. For unique ad unit sizes, our system will need some time before it can optimize the number of ads shown. Please see our blog post Understanding the dynamics of the AdSense auction - Part II for more information. Here are three examples of custom-sized ad units displaying text ads:
For display ads, our system will determine the appropriate size ad to fit into the space you select; the selected ad will not be larger than the space requested. In the example below, we’ve shown the same three custom sizes as above, but this time with display ads. Please note that the dotted border is only present to show the total size of the ad unit, but won’t actually appear on your pages.
To ensure that ads continue to deliver a positive user experience, we’ve put a few restrictions in place around maximum and minimum pixels for ad sizes. Any custom ad size that falls outside of the restrictions won’t appear on a page. As always, all of your ads must adhere to the AdSense ad placement policies. Remember that users value your content, and that they appreciate a balance of content and ads, knowing that the ads support the content creator. Forcing too many ads into the users viewable screen is not likely to tempt them back to your site.
Ready to get started with custom ad sizes? Create an ad unit in the usual way, select “Custom ad size” from the Ad size drop-down and set the desired width and height for your ad unit in the process. Copy and paste the ad code into the HTML source code of your page where you'd like the ad to appear.
You can also find more information in our Help Center. We’re excited about the possibilities of these new custom ad sizes, and appreciate your ongoing feedback as we continue to improve this offering. Please feel free to share your thoughts and suggestions about this update on our Google+ page.
Posted by Omer Gimenez Llach - AdSense Software Engineer & Johan Land - AdSense Product Manager