• by Mark Walsh , June 4, 2010

When it comes to in-stream video ads, 15 or 30 second spots are the standard. But what's the optimum length for a branded video or in-banner video ad? Thirty seconds to 1:30, according to new data from video ad and analytics firm TubeMogul.

The completion rate for standalone video ads of that length, at 32.2%, compared to 23.4% for ads longer than 1:30, and 17% for ads under 30 seconds. The assumption would be that the shortest ads would've had the highest completion rates. "But what people seem to be saying is: 'we don't like 15-second TV-style spots or longer branded content, but rather short, interesting viral clips,' said David Burch, communications director at TubeMogul.

The findings were based on sample of 100 top video ad campaigns, spanning 19.7 million views from viral and paid placements (click-to-play 300 x 250 units), and included brands such as Hyundai and Microsoft.