comScore: The Average YouTube Viewer Watches 5 Hours Of Videos A Month

comScore has just released its monthly data on online video engagement, with 176 million U.S. Internet users watching online video content in May for an average of 15.9 hours per viewer. The total U.S. audience engaged in more than 5.6 billion viewing sessions during the course of the month. And 83.3 percent of the U.S. Internet audience viewed online video.

comScore says Google sites (a.k.a. YouTube) was again the top video property in May with 147.2 million unique viewers, 2.17 billion viewing sessions and an average of 311 minutes spent per viewer on the site (that’s an average of 5 hours spent per view in May).

YouTube had previously revealed that the video site is now handling 3 billion views per day, but comScore’s measurement of viewing sessions is different from actual views. We’re assuming a viewing session is measured as sitting in front of YouTube before clicking away, which could include watching 1 video or 10 multiple videos in a single session. YouTube is probably counting individual views.

VEVO followed with 60.4 million viewers (and 309 million viewing sessions), with Yahoo (55.5 million viewers) and Facebook (48.2 million viewers) taking the third and fourth spots, respectively. Viacom Digital ranked fifth with 46.5 million viewers.

The U.S. internet audeince viewed a whopping 4.6 billion video ads in May (up from 3.8 billion in April), with Hulu generating the highest number of video ad impressions at more than 1.3 billion (up from 1.1 billion ads in April).

Tremor Media Video Network ranked second overall (and highest among video ad networks) with 700.8 million ad views, followed by (642 million) and BrightRoll Video Network (565 million). Time spent watching videos ads totaled more than 2 billion minutes during the month, with Hulu delivering the highest duration of video ads at 560 million minutes.

Video ads reached 45 percent of the total U.S. population an average of 34 times during the month. Hulu also delivered the highest frequency of video ads to its viewers with an average of 48 over the course of the month.

The duration of the average online content video was 5.2 minutes, while the average online video ad was 0.4 minutes. Video ads accounted for 12.6 percent of all videos viewed and 1.2 percent of all minutes spent viewing video online.