Ave Session time bug?

  • 11 January 2021
  • 2 replies

Badge +1

I’ve created a calculated field for session time by doing this:

Which gives me what I would expect when plotted over the last 30 days:

You’ll notice that the max is 13.9 and the min is 1.8 and looking at the chart the average is probably in the region of 7 or 8 minutes.

However, when I change this to a table:

I get an *average* of nearly 31 mins.


So have I done something wrong? How can I get a 30-day average session time (that’s all I need to go on a dashboard)? Or, is it a bug?


Best answer by cherise 21 January 2021, 01:14

View original

2 replies

Userlevel 6
Badge +3



Thank you for reaching out! I noticed that you also wrote into support and are working with our support engineer @enague on this! You are in great hands. 

Badge +1

@cherise I have been working with support to try and understand this, but the response back from support suggests that I can’t actually get to the number that I’m after so it would be good to get a product gap logged.

For anyone else’s benefit who is trying to understand average session time, here’s the explanation from Mixpanel support:


Let's use you and me as an example. I do a session once monthly for 10 minutes, and you do a 10 minute session every day of the month. In the line graph, the sum per user will be 10 every day because it is either a day where we both do 10 minutes (average of 10), or it is a day where it is just you (also average of 10). However, in the bar graph, it takes the total minutes of 310 and divides it by 2 total users, which equals 160. This explains why the 33.1 number seems so much higher than the daily average on the line graph.


What I was expecting to see, using the example above, was an average of 10 minutes because no user has spent anywhere near 160 minutes in a single session, never mind on average. I’m guessing a number of 160 must make sense in someone’s world but when I’m trying to understand typical use of our audience, thinking people are engaged with our website for an average of over 2.5 hours when no one spends more than 10 minutes is just nonsense.