Larger online audience size does not necessarily translate to more ad views. Web research firm comScore’s recently released data makes it clear that the size of the online audience is not a good predictor of the number of ad views. Specifically, YouTube has the largest online audience of all Internet destinations with 144 million viewers last month alone. In addition, the site had the greatest engagement with an average time of 4.3 hours spent for the month per viewer. Yet Hulu, with a mere 24 million viewers during the same time period and only 2.2 hours per viewer, generated more than twice the amount of video ad views. Hulu had 556 million video ad views in June while Google Sites (mostly YouTube) had just over 200 million. This translates to 24.2 ads per Hulu viewer and just 4.3 ads per YouTube viewer.

Other sites with strong online audiences include Yahoo with 45 million viewers as well as Vevo (a music video site) and Facebook, each with more than 43 million. In terms of ad views, video ad network Tremor Media ranked second behind Hulu with 524 million ad views. BrightRoll (another ad network) came in third with 333.5 million and Microsoft sites followed with 222 million ad views.