# Session Length 90th percentile vs 10th percentile

Hello guys
I had a look at my session length and I noticed 2 unfamiliar parameters under the session length tab:
90th percentile and 10th percentile, can someone please explain to me what dose 2 values mean.
Thanks

Hey there Max_power1965! Thanks for reaching out. The parameters you’ve outlined show the session lengths that fall in the 10th percentile & 90th percentile. (from Google) Within a set of data, the n-th percentile describes the value below which n% of the data, when sorted, fall. For example, within the integer sequence spanning from 0 to 100, 50 is the 50th percentile or median, 10 is the 10th percentile, and 90 is the 90th percentile.

To use your screenshot as an example, this means that if you have 100 sessions, ordered from shortest session to longest session, the 10th shortest session would be 1m 21s, the 50th (or median) would be 7m 7s, and the 90th would be 35m 54s. There could be 9 more sessions at 36m, 50m, 2h, 6h, for example, but the 90th would be 35m 54s.

I hope that helps!

Randy

You can also read that as:

• 10% of your sessions are shorter than 1m 21s
• 50% of your sessions are shorter than 7m 7s
• 90% of your sessions are shorter than 35m 54s