Video advertisements are, by their very nature, intrusive but when an ad appears during the middle of a video viewers are more likely to stick with it for the duration. A new report from Akamai in collaboration with the University of Massachusetts, studied 367 million online videos and 257 million videos ads, watched by 65 million global viewers in one 15 day period in April 2013 to gauge the mood of the viewing public. “Understanding the Effectiveness of Video Ads: A Measurement Study”, the largest scale scientific study of video ad efficacy ever, used anonymous data to track how viewers engaged with different ad formats and how they reacted to issues with slow loading and buffering.

Key Findings Of The Effectiveness Of Video Ads Report:

• Viewers are more likely to sit through the whole of a mid roll (18.1%) than the same ad as a pre-roll. But pre-roll ads have a 14.3% completion rate compared to the same ad as a post-roll.

• Viewers are much more tolerant of video ads than they are of videos that take a while to load. Viewers who had to wait for around 10 seconds (the horror) for their video to load were three times more likely to abandon the ad than users who spend the same amount time watching a pre-roll ad.

• Users who abandon ads will do so pretty early. 33% leave at or before the quarter-way mark and 66% at or before the halfway mark in the ad.

• Ads that play within long-form content complete at a higher rate (87%) than those that play in short-form content (67%).

• The report found that the time of day and day of week did not have much of an affect on completion rates.

Pre-Roll Abandonment 5 x Higher Than Mid Roll Abandonment

Viewers were more inclined to automatically skip a pre-roll ad as soon as they could compared to an ad that was presented to them during the video. This seems logical for two reasons: #1) the viewer is already invested in watching and if they are engaged, they will put up with with an ad if it means they get to watch the rest of the video and #2) most of us are used to sitting through a set of ads halfway through a TV show so we are used to being interrupted in this way.   

ad placement

Sports Fans Have Little Patience For Slow Loading Videos

Sports fans are five times more likely to abandon a video, and its pre roll ad, at start up if the content takes more than 2 seconds to load. Those watching news content are more inclined to stay with the video during loading issues, however, they are 13 x more likely to abandon watching if rebuffering lasts more than 2 seconds per minute.

start ups


The full report is available as an downloadable .pdf here and there is also a white paper available on the findings.

  • LeoUrushi

    This passage seems a bit misleading; "Viewers are more likely to sit through the whole of a mid roll (18.1%)
    than the same ad as a pre-roll. But pre-roll ads have a 14.3% completion
    rate compared to the same ad as a post-roll."

    Original wording in the report reads; "We show that an ad is 18.1% more likely to complete when placed as a mid-roll than as a pre-roll, and 14.3% more likely to complete when placed as pre-roll than as a post-roll."

    The overall message won't change. But 14.3% is not the actual completion rate.

  • Eduardo Corral

    I honestly have less patience for midroll. I usually either watch tutorials or listen to long works of music. When my content is being constantly interrupted I change my content. In the case of tutorials, unless it's extremely important I'm far more likely to go to documentation or simply figure it out on my own rather have to sift through something that takes away my concentration from the task at hand.

  • Rula Brown

    The results indeed seem logical, but it would be most interesting to find out about the difference in click through rates. Considering that click throughs may be a specific objective of many video ad campaigns. Are users inclined to click away if they're engaged in "their" video? A rhetorical question?