It's important to note that the 20% rule only applies to text that covers images attached to your ad. It does not include text on your ad outside of images, like the description copy or call-to-action button.
There are a few exceptions to the 20% rule, including images of book covers, album covers, event posters, video games, and some product images that contain text (e.g., a cereal box). Text-based logos are not an exception to the 20% rule, and will be counted as text when Facebook reviews your images.
So, why exactly does the Facebook 20% rule exist? It all comes down to what users want to see and engage with in their newsfeeds. Ads with less overlay text actually perform significantly better than images crowded with text, so the rule actually creates a better experience for both users and advertisers.
Facebook Text Overlay Tool
When Facebook reviews your ad images, they examine how much of your images are covered by text. While you're creating an ad, it can be tricky to evaluate the exact percentage of text covering your image -- fortunately, Facebook provides a tool you can use to check before you even submit your ad for review. You can access that tool right here.
Here's an example of an image with an ideal amount of text:
In the next example, there's an extra line of text:
This final example is exactly what Facebook does not want to see:
Here's a simple rule to remember: the best way to capture users' attention on Facebook is to use an eye-catching image with no text. The 20% rule isn't just an arbitrary standard -- it helps advertisers reach their target audiences more effectively, and prevents users' newsfeeds from becoming overwhelmed with disruptive advertisements.
Originally published Jun 20, 2019 7:00:00 AM, updated June 20 2019