This is a basic concept but most analysts and professionals who consume data from Google Analytics do not know exactly what the “Users” metric within GA means.
Failure to understand how this metric is handled by GA can lead to errors in analysis, which in turn can lead to wrong business decisions.
To understand it a little better, let's see how a user is defined within Google Analytics.
How are “Users” defined in GA?
“Users” in Google Analytics is the number of new and returning people who visit your site during a given period.
On a person’s first visit to your site, a GA cookie will be set and an identifier will be assigned to them. If the same person accesses your site 10 times through the same device / browser (preserving cookies) they will still be considered as a single user.
Note that I mentioned that an identifier is assigned to the visitor. This identifier lets you know if this is a new or returning visitor. I find it convenient to talk a little more about this identifier to clarify some topics in the sequence of this article.
“Client ID” in Google Analytics
The “Client ID” is formed by the combination of a random number plus a first timestamp of the visitor's access (timestamp).
You can view this identifier from the GA cookie, accessing your cookie history through your browser or a specific extension to do so.
The first field,
GA1, refers to the version of GA used.
The second field,
2, refers to the number of domain components separated by periods. By default the GA cookie is set for the top level domain as dilmarames.com. Since we have two components (dilmarames and com - separated by a dot) the value is 2. If we had, for example, analytics.dilmarames.com, we would have 3 components (analytics, dilmarames and com) and the value of this field would be 3.
The third field of the Google Analytics cookie,
413566523, refers to a generated random ID.
The fourth element,
1568150771, is the timestamp, which is generated when the user first accesses.
The third and fourth elements form the “Client ID”, which in this case will be
How does GA count new and returning visitors?
When a visitor first accesses your site, the Google Analytics tracking code generates a “Client ID” and sends it to GA servers.
This ID identifies a new user. Every time a new ID is detected, a new user is counted in Google Analytics. If GA identifies a pre-existing ID in a new session, it will be considered a returning visitor.
It's important to highlight:
- If the user deletes cookies from their browser, the ID will be deleted. Consequently, on your next visit you will be classified as a new user;
- If the user accesses your site through another browser / device, it will be counted as a new user, since the ID exists only in the browser / device in which it was created. For this reason we cannot use “Client ID” to track users across multiple devices.
Read too: "What are sessions in Google Analytics?“
Google Analytics does not report unique users
Contrary to what many people think, Google Analytics does not report unique users.
It is common to see clients and analysts presenting commercial materials and reports indicating “unique users” and referring Google Analytics as a source. This is a misconception.
According to Google itself, the “Users” metric refers to new users and returning users.
Evidently, if the “Users” metric refers to new and returning users, then it cannot refer to unique users.
But then, where are the unique users?
GA does not report unique users. It is.
To identify a user through various devices / browsers, it is possible to use the “User ID”(Not to be confused with the“ Client ID ”generated in the cookie).
The “User ID” is a code linked to a single user from that user's engagement (usually through an account / login) in one or more sessions started on one or more devices. GA interprets each “User ID” as a separate user, which results in a more accurate user count in reports.
When you submit a Google Analytics code (Client ID) and related data from multiple sessions (User ID), your reports tell a more unified holistic story about a user’s relationship with your company.
New + returning users do not match the total
The number of total users reported by GA will rarely be equal to the sum of new users and returning users.
This is because Google Analytics also counts a new user as a returning user if they visit the site again within the observed range. There is an overlap of new and returning users.
Many analysts subtract the number of new users from the total number of users thinking they have found the number of returning users. This methodology is not correct.
Google Analytics does not bring any metrics by default for returning users. If you want to analyze browsing data for these users, you will need to apply one of the standard GA segments.
Same user classified as new and returning
As I mentioned earlier, a user can be classified as a new user and a returning user.
Suppose you are reviewing your audience report for the period from 01/03 to 03/31. A visitor visits your site on 3/5 and again on 3/20. It will be counted as a new user (3/5) and as a returning user (3/20). We are assuming a normal condition where the user does not delete cookies, does not use any type of blocking cookies or browsers that remove this information after a few days.
Read too: "The era of browsers in digital advertising“
This is also true for the source and medium of the traffic. Going back to the previous example, if our visitor accesses on 03/03 through organic search and on 03/20 through a Google Ads campaign, we will have a session started via organic (03/05) and one with paid origin (20 / 03) accounted for in GA.
Always pay attention to the scope of metrics and dimensions in your analysis.
Remembering that in GA "Users" have scope for "User" and "Sessions" have scope for "Session". To learn more read the article “Dimensions and metrics in Google Analytics“.
Why are "Users" important in Google Analytics?
I think it is redundant to talk about the importance of the “Users” metric within Google Analytics. Virtually all business analyzes are linked to this metric.
The metric of new users lets you see how many people visited your site for the first time in a specific period. This metric can indicate the success or failure of your marketing actions from the generation of new users.
The metric of recurring users indicates how many people returned to your site. For sites that publish content regularly, a large number of returning users can indicate that they find your content valuable and are returning to consume more.
We saw how users are defined within Google Analytics and how the “Client ID” is generated.
I highlighted the fact that GA does not report unique users and that in order to see metrics for returning users, we must apply segmentation.
We have entered into the way that GA counts the “Users” metric and that a user can be classified both as a new user and a returning user within a certain period.
I hope this article helps web analytics professionals to better understand the metrics of users in Google Analytics, thus avoiding errors in their analysis.
Read too: "What are pageviews in Google Analytics?“