Viewability
Viewability measures whether an ad had the opportunity to be seen "” defined by industry standards as a minimum portion of the ad being on screen for a minimum length of time.
Key takeaways
- Viewability measures the opportunity to see an ad, not whether it was seen.
- The MRC standard: 50% of pixels in view for 1 second (display), 2 seconds (video).
- It is verified by accredited third-party measurement vendors.
- Viewability is a floor for quality, not a measure of attention or impact.
The standard
The Media Rating Council (MRC) defines a viewable display impression as at least 50% of the ad's pixels in view for at least one second, and a viewable video impression as 50% in view for at least two seconds. This gives buyers a consistent benchmark for whether inventory could have been seen at all.
Viewability is not attention
A viewable ad is one that could be seen, not one that was noticed. The industry has moved toward attention metrics "” using eye-tracking panels and engagement signals "” to go beyond viewability's blunt on-screen test toward whether the ad actually captured focus.
| Measures | Opportunity to be seen |
|---|---|
| Display standard | 50% pixels, 1 second (MRC) |
| Video standard | 50% pixels, 2 seconds (MRC) |
| Beyond it | Attention metrics |
Frequently asked questions
What counts as a viewable impression?
Under the MRC standard, a display ad is viewable when at least 50% of its pixels are on screen for at least one second; for video the threshold is two seconds.
Is viewability the same as attention?
No. Viewability confirms an ad had the chance to be seen; attention metrics attempt to measure whether it was actually noticed and engaged with.