The Facebook 20% Rule: Why Your Ads Might Not Be Running

The old Facebook 20% text rule. Until recently, Facebook advertisers were allowed to cover their ad images with no more than 20% text. To adhere to guidelines, those who paid for reach on the platform were forced to use a tool developed by Facebook that divided ad images with a 25-rectangle grid (it’s since been replaced with a different tool, but more on that later).

https://instapage.com/blog/facebook-20-text-rule