Over the last month, the FP1 digital team tested 3, 6, 15 and 30 second Facebook video ads to gauge the most effective video length for completed views and user engagement.
While conducting this test, we found a strong correlation between age and average video watch time. The youngest age group (18-24) had an average completion rate of 35% with an average watch length of 2.4 seconds, while oldest age group (65+) had an average completion rate of 64% with an average watch length of 5.2 seconds.
Most surprising, however, was the indication of diminishing marginal returns with video lengths. For all video lengths, except the 30 second videos, average watch time increased with the length of the ads.
Our 30 second videos not only had the lowest ratio for average completion rate (12%), but users had also watched less (3.6 seconds) than the 15 second ads (4.3 seconds).
Finally, for all age groups, the average completion rate decreased an average of 50 percent between each video length. For example: in the 45-54 age group, average video completion rate dropped from 53% for the 6 second ad, to 27% for the 15 second ad. This remained consistent between the different video lengths and age groups.
Two main takeaways: