Performance
Viewability: what the advertiser actually buys
The MRC/IAB standard defines a viewable display impression as 50% of pixels on screen for at least 1 second (2 continuous seconds for video). Impressions served below that exist in the report but are worth little at auction.
That's why demand pays more for high-viewability formats: an anchor is visible practically 100% of reading time; in-article video fires exactly when it enters the screen. The banner buried in the footer serves impressions nobody sees.
For the publisher, viewability is a price lever: the same traffic, reorganized into visible formats and positions, raises the average value of the inventory without a single extra pageview.
In the initial analysis we map exactly that: where the site serves invisible impressions, and which formats convert the same attention into impressions demand pays dearly for.
Sources and reading
Media Rating Council · IAB