Google Analytics 4. How events are different from Universal Analytics

What is an ‘event’ in GA4?

This is where Google Analytics 4 gets a bit confusing.  Because everything is an event!

In Universal Analytics:

Events are interactions you want to track, in addition to page views.  Things like PDF clicks.  Email clicks.  Scrolls,  Video plays etc… Events needed to be tagged in addition to the standard page view tag.

In Google Analytics 4:

An event is any distinct action occurring at a distinct time associated with a user in your app or on your website.  Every hit sent is an event.  The following are examples of events in Google Analytics 4:

* Page views – a hit for every page view, the same as Universal Analytics (event name = page_view)

* Scrolls – a hit for the first time 90% vertical depth becomes visible on the page (event name = scroll)

* Outbound link clicks – a hit for each time a user clicks a link that leads away from the current domain (event name = click)

Automatically collected events

When you setup a GA4 property (I posted instructions on setting up GA4 here), and you’re firing your GA4 script on the page, then it will automatically collect the following events:

1.   page_view (page views)

2.  scroll (the first time 90% vertical depth becomes visible on the page)

3.  click (each time a user clicks a link that leads away from the current domain)

4.  view_search_results (each time a user performs a site search, indicated by the presence of one of the following URL query parameters: q=, s=, search=, query=, keyword=)

5.  video_start (when the video starts playing)

6.  video_progress (when the video progresses past 10%, 25%, 50%, and 75% duration time)

7.  video_complete (when the video ends)

8.  file_download (when a user clicks a link leading to a file (with a common file extension) of the following types: document, text, executable, presentation, compressed file, video, audio)

Events (2) > (8) above are enhanced measurement events.  I.e. these are the events which GA4 captures without the need for any additional code or tags.  You can see these in Admin > Data Streams > Click on the Data Stream.  These will be activated as default when you setup a GA4 property, although you can edit them:

Event structure in Google Analytics 4

In Universal Analytics:

Events have a tiered naming hierarchy: category, action, label (optional) & value (optional).

In Google Analytics 4:

Each event has a name (obviously), which is either automatically assigned, or customised.  Events also have optional parameters, which can provide further information about that event.  An event can have up to 25 parameters:

For example, PDF downloads could be labelled like this in GA4:

With GA4, you get to append more information to events which is great.  Although you can’t categorise and sub-categorise them like you can with Universal Analytics.  I.e. event categories > drill down into > event actions > drill down into > event labels.

What next when setting up events in GA4?

Once you’ve setup GA4, you’ll see data on your automatically collected events in the Engagement > Events reports.  Click on an event to view data for the parameters associated with the event.

If you are looking to track the same events in GA4 as you have in UA, then you might not need to setup any additional tags, as some of them might be automatically collected (e.g. video_start, file_download).

However, some of these automatically collected events might not use the names you want to use.

And the chances are, you want to send more of your own events into GA4.  These will need tagging in GTM.