The optimal duration of a viral video is 77 seconds.

Discussing the stated limit on the length of the video (3 minutes) with the participants of the " Komediyadi ", I decided to go and count, but what is the actual length of the clips that hit us in the chart on VirusVideo.ru (every day the editors go through the tops of video hosting sites, select the most interesting and announce - such a daily chart can be received in the mailing list). I counted in the last 8 days, it turned out that the average duration is 1:47. And if you take not the average, but the median, which is more correct - 1:17. It turns out a beautiful figure of 77 seconds.
I asked colleagues from Rutube , what statistics on their tops. If you take active clips, then the median for the top 10% by the number of views and estimates is 71 seconds. If you take the top 1% only by rating - 60 seconds, only by viewing - 109 seconds.
Moral: 3 minutes is too long for a viral video. The optimal duration is from one to one and a half minutes. However, our number 77 I like the most - it is round. And we have in the ranking not only Rutube, but also Youtube (and Western videos), and some other hosting sites. Theoretically, for us and Americans data may differ. However, 71 or 77 seconds is already within the margin of error.