Now that you have a better idea of how to improve your viewability, you can start to understand how to calculate viewability. The standards of this measurement are always evolving as this method of advertising is popularizing. And the industry at large hasn’t fully adopted the current guidelines, so the definition may vary depending on individual marketers and media providers.
That said, there are a few existing guidelines that are generally considered standard in the industry. First, as discussed previously, an ad is typically considered viewable by the IAB and MRC when 50% of pixels are in view for at least one second. Video ads require a bit more—they’re considered to generate viewable impressions when they’ve been in view by a user for at least two seconds. And larger desktop ads only require 30% of the pixels to be in view. However, these viewability measurement standards do not apply to custom ad units—those have yet to follow a consistent standard.