Policy FAQs for mobile optimized (multi-screen) websites
When building your multi-screen website, it's important to ensure that your site complies with the AdSense program policies. To help you get to know our multi-screen policies even better, we've put together these frequently asked questions from AdSense publishers.What's the Google AdSense mobile ad placement policy?
AdSense's responsive ad code is designed to automatically adapt the ad unit size to your page layout. If you find that our responsive ad code doesn't do everything you need, you may modify the ad code to specify either a general shape (horizontal, vertical, and/or rectangle) that your ad unit should conform to or an exact size for your ad unit via CSS. Learn more about the advanced features of responsive ad code.
As long as the main content stays above the fold and doesn't affect the user experience, you could consider implementing a 320x100 as an alternative. Please refer to our policy on ad limits for more information.