how many values can a custom dimension take in google analytics?

Question

To anonymously analyze users flow and engagement I want to use the ClientID, as identifier of each user, as a value of a custom dimension. I have two questions regarding this idea:

• How many values can be associated to a custom dimension? This will determine the feasibility of this approach or not.
• Is there any other approach to track individually, yet anonymously, users activity?

Answer 1

I'm not aware of a limit though for custom dimension length. But storing userId, sessionId customerId and timestamps for all hits in custom dimensions is not all that unusual these days. Here is a link to a post by Simo Ahava's post Improve Data Collection With Four Custom Dimensions on how to set it all up in google tag manager.