Viewability

Viewability is the probability that a served impression was actually in front of a human's eyes. In web display, the MRC standard is 50% of pixels in the viewport for 1 second (2 seconds for video). In CTV, it's the full playout reaching a device with the screen on. In DOOH, the working definition is: the playout completed without screen-side error AND the audience-on-screen during the playout was greater than zero.

Modern sensor-equipped screens (Trillboards being the canonical example) tighten that further: viewability requires per-person dwell time on the playout to exceed slot length minus a 2-second tolerance, AND attention (gaze direction + head pose) to register at least "medium" during the playout. The combined metric is the DOOH equivalent of the MRC's "viewable second" — sub-second precision via edge inference.

Industry-wide viewability for programmatic DOOH was ~73% in 2026 per Magna's benchmarks. The headline gap (vs. CTV's ~95%) is mostly venue-side: a screen above a bar register where everyone's facing the bartender will measure poorly no matter how clean the playout is. Sensor-equipped inventory cracks 90% because attention is measured rather than assumed.

Viewability is the multiplier on raw impressions when calculating eCPM: viewable-impression CPM = raw CPM ÷ viewability rate.