Usage Frequency
IntermediateUsage frequency is how often a single user returns to a product within a defined window, usually counted as active days or sessions per user.
Usage frequency is a per-user rate, not a volume, and the number means nothing until the window and the qualifying action are fixed. The term is not standardised across the industry: some tools count active days in a period, some count sessions per user, and some count occurrences of one named event. The common trap is reporting the mean. Frequency distributions are almost always skewed, so a small heavy-use minority lifts the average while most users appear exactly once, which is why the median and the shape of the distribution belong next to it.
How it is calculated
Usage frequency = total active days across users in the window ÷ number of active users in that window
An active day is a day with at least one qualifying action, counted once regardless of how many actions occurred. The unit is days per user per window. Counting sessions instead of days changes the unit, and the two numbers are not comparable.