How to Set Up Event Tracking in GA4 With Google Tag Manager

What Event Tracking Actually Means in GA4

Conversions can differ for different websites. For some, a simple tap on the Call button could be a conversion. For some, it could be capturing a qualified lead using a lengthy B2B contact form.

Let’s say you are running an Ads campaign, and you check your dashboard to see you have had more than 5,000 clicks on your ads. You open Google Analytics to see how much engagement and how many conversions your ads received. You do not know how many visitors actually filled out the intended form or downloaded your brochure as a PDF.

This is where the event tracking comes into play. Every action a user takes on your site is an event that carries specific information. GA4 tracks some of this information on its own; however, some you need to create manually. This is what we will cover in this guide. What does GA4 track on its own, which events need to be created manually, and how can you create them using GTM?

What GA4 Already Tracks on Its Own

Since Google Analytics evolved from “Universal Analytics” to the current GA4, quite a few things have changed. Previously, Universal Analytics used a hit-based model, where pageviews and events were separate hit types, and for events, we had to use category, actions, and labels. However, under GA4, everything is an event. From page views to scrolls, downloads, and clicks, everything is categorized as events, making tracking much more streamlined once you get the hang of it.

In GA4, events such as first_visit, session_start, and user_engagement are automatically tracked once you install it on the site. Also, with the help of Enhanced Measurement, one of GA4’s features, you can track additional events such as scrolls and outbound clicks. Although there are some limitations here, for example, the scroll event only triggers when a user reaches 90% of the page depth; sometimes, if a user subscribes to your newsletter, it might be recorded as a “form_submit”.

That is why, for any actions not already covered by Google, it is necessary to create custom events and mark them as “Key Events” if they are a conversion for your business. A “Key Event” in GA4 is something that you feel is the most important action for your business. A desired action you want the user to take. It could be a phone call, an email newsletter subscription, a form submission, a page visit, a PDF download, or something else.

Previously, Google called them conversions. They renamed it “Key Events” in March 2024. As we have already mentioned “Custom Events”, we will discuss how you can create custom events using GTM, which events you should be tracking, and how you can track them.

How Event Tracking Changes with Your Business Types and Needs

There is no defined list of events your website should track. It depends on what your business needs from your website. For a local vet service, a phone call is as important as filling out a form. However, for a B2B engineering business, getting a qualified lead using a detailed form is the only action that matters. Sometimes, you want to know how many users have downloaded the PDF guide you listed on your website a long time ago.

For an E-commerce website, tracking the whole funnel and user journey is just as important as tracking the conversions. For a content website, you need to track newsletter sign-ups, video plays, etc.

Always remember, you do not need to track every action on every page of your website. However, sometimes tracking random events, even for a while, makes sense for understanding user behavior on your website.

Also, keep in mind that not all custom events need to be marked as key events. Sometimes, you can create a custom event to understand user behavior and identify opportunities to improve your site.

GTM building blocks(containers, tags, triggers, variables)

Before we move on to the basic building blocks of Google Tag Manager, make sure you have GTM installed and set up on your site. Also, you need to understand the elements in the right order. To make it easier for you to understand, we have explained them below:

Container: It is the single piece of code installed on your website that holds everything else. You make the changes and publish the container, and everything will be live on the site without you having to modify that code again. This is the primary utility of Google Tag Manager. Your team can make a host of changes to your website without affecting the live site.

Tag: It is an instruction that fires and sends the data somewhere. In our case, we will use the Tags to send the events to GA4.

Trigger: As the name suggests, it is a condition that causes the Tag to fire and send data. They come in handy whenever you are designing complicated Tags that you only want to be fired when certain conditions are met.

Variables: Pieces of information that GTM reads at that moment. For example, the URL of the link that was clicked when a user clicked on a Call-To-Action button. Triggers use variables to make decisions, and tags use them to add details to events.

Below, we have given an example of the final workflow in Google Tag Manager’s mechanism:

When a user clicks a call button on the site, GTM reads the Click URL variable and checks it against the trigger we have set up, which fires only on links starting with “tel:”. Then the trigger fires our tag, which sends an event called “call_button_click” to GA4.

Creating different types of event tracking tags in GTM(Step by Step)

Now, as we move toward the most important part of this blog, we will learn how to create different types of event tracking tags in GTM. In most cases, these two examples cover the two most important setups for tracking events in GA4. Once you learn how to create the tags and get used to the interface and logic of GTM, you will be able to understand and create tags for the other aspects of tracking various events on your site. Also, most steps will be the same for most tags, so you can replicate them as you go.

Tracking a specific button or CTA

This is one of the most common tracking tags you’ll need. How to track a specific CTA or a button on some or all of your site pages. Let’s assume that you want to track the “Get a Quote” button. The following are the steps you need to follow:

Make sure GA4 is active and receiving the data in Realtime and Reports.
Now open your GTM container, go to Variables, click Configure, and enable the built-in Click variables.
We would need a unique identifier for the button that we want to track. This is easy to get: open the page with your CTA. Right-click the button, select Inspect, and look at the highlighted code. Most buttons have a unique identifier, such as an “id” or “class”. Note down or copy whichever you want to.
Now go to “triggers”, click new, and choose the trigger type “All Elements”. Then choose “some clicks”. After that, set the condition using the identifier you found, i.e., Click ID equals or Click Classes contains. (Always remember that these identifiers may change) with the change in design of the site or themes. So, always keep auditing the setup and keep your developers in the loop.
It is time to create the tag. Go to “Tags” and create a new Tag. Afterward, choose “Google Analytics: GA4 Event” as the tag type. Enter your GA4 measurement ID in the box so that the event is sent to the correct property.
Now you can give the event a name of your choice. Just remember two important rules: the name should be lowercase without spaces; instead, you can use underscores. Your event name can look something like this: “cta_quote_click”. Also, make sure you are not using any pre-existing event names from GA4, such as “form_submit,” as you will not be able to differentiate them in the reports later.
You can add parameters to be sent with your event. Always remember that GA automatically attributes the event to the page, so you do not need to add that as a parameter.
Scroll down to the trigger and choose the one you created specifically for this tag. Finally, you can save the tag and preview it to see if the tag is firing and appearing in the Realtime report in GA4. If everything works, publish your container, and you are good to go.

Tracking Call/Mail button Clicks

Phone clicks are easier to track because their links contain “tel:”. You do not need to inspect to find unique identifiers. This time, you can create a custom trigger, choose the type “Just Links,” and then select “Some Link Clicks” with the condition that the clicked URL starts with “tel:”. You can follow the same steps as above to create the tag, choose an appropriate event name, and then choose the trigger you created just now.

This is the same step you can follow to track the mail button clicks as well. Just one difference: in the “Trigger” for “Some Link Clicks,” the condition changes to “mailto:” because all the mail button links start with “mailto:xyz@companyname.com”

How to track different types of forms(with thank you, without thank you)

Form Submissions are still probably the most important event that businesses want to track because the forms help you capture a lead from your site. We have already discussed above that you can track CTA button clicks; however, it is always possible that, after that, a form submission may have timed out, failed validation, or errored out. Thus, it is necessary to track a form submission with a separate method. Remember, no method is foolproof, and your tracked event numbers may still differ from the actual number of captured leads, but our goal is to be as close as possible to the actual number.

Following is the first method, which is widely used and is easier to track:

Forms with a thank-you page

This is one of the simplest ways you can track form submissions. Once the user submits the form, they are redirected to a custom-built thank-you page. You can use the Page View trigger type for the thank-you page with the condition that the Page URL contains “/thank-you/” or use the URL of your custom-built thank-you page. Again, attach this trigger to a new GA4 event tag, and name your event like “generate_lead,” and that is it. Always make sure the thank-you page is only accessible to a user after they submit the form, so the numbers are not skewed.

Also, make sure it is set to “noindex” so that Google or any other Search engine does not index it. Sometimes a user can keep the page open in their browser or refresh it multiple times, which may also skew the data. Thus, constantly check the number of Users who have submitted the data and match it with the Event submission count.

Also, if you have different types of forms on your site and want to track them separately, you can create multiple thank-you pages with different URLs and set up a separate event for each. You can also add a condition of “Page Referrer” in your Trigger so that you can create and track form submissions from different pages separately.

Forms without a thank-you page

Some platforms have forms that submit the data in the background without reloading the page. The form submission success message will appear on the screen, and that is it. We can also track these submissions using the Data Layer. The Data Layer is like an empty notice board on every page, where the website or plugins can write messages. GTM can read those messages, and we can use them to create Tags to capture the events. So, whenever a form is submitted, the plugin writes a message on the board saying the submission was successful.

Check if the form plugin writes a success message to the Data Layer. In GTM, create a trigger of type “Custom Event” and enter the message that your plugin is using. To find the exact message, we recommend asking your developer for assistance, as it varies by plugin.

If the plugin does not write anything to the Data Layer, you can dynamically track the success message that appears on the screen. You can choose the “Element Visibility” trigger, which fires when the message appears on the screen.

The third method is to have your developer push a custom success event to the Data Layer after the form submission is confirmed.

One trigger we do not recommend is the GTM’s built-in “Form Submission”. Many forms never use the browser mechanism they rely on, and sometimes it can fire even when validation fails.

iframes and CRMs

Some booking tools and CRMs embed their forms in an iframe, which is a box or section on your website that displays content from another website. For security reasons, GTM cannot see the activity inside the box, such as clicks, scrolls, and submissions.

If the form is inside an iframe, check whether the provider gives an option of sending the event to GA4 automatically, or you can integrate the Data Layer or configure the form in such a way that it redirects to a “thank-you” page on your own site after submission.

How to test events separately in GTM & GA4 & how to mark them as key events

Most users create the Tag in GTM and preview it to check whether the Tag is firing, then assume it is done. But the tag firing in GTM and GA receiving the data are two completely different things.

Start in GTM, click Preview in the top-right corner, enter the URL where you want the tag to fire, and a debug panel will connect to your site. Complete the process, such as filling out the form or clicking on a specific button. In the panel, check if your tag appears under the “tags fired” section once you complete the process. Also, make sure the tag does not fire on any activity that does not meet the trigger conditions you set.

Simultaneously, open GA4 and check the DebugView and Realtime. When you preview the URL in GTM, the data will be sent to the DebugView and the Realtime reports in GA4. Make sure the correct event name appears there, and that the parameters are also present when you click and open the event.

Once everything checks out in the DebugView, publish your container. Give your new update a unique name and include all the details of the activity performed in this version. Finally, do a final check in incognito mode to confirm that the event is firing in GA4.

The final step is to mark the Custom Event created as a “Key Event”. Your event will appear in the list once it has been fired at least once. Also, the standard Reports might take 24 to 48 hours to populate with the Custom Event, depending on how frequently it gets a hit. You can mark any event as a key event by going to Admin > Events and clicking the star.

Bonus Tip: If you have added custom parameters in GTM and want to see them in the reports, you also need to register them as custom dimensions in the GA4 admin. Without this, the parameters will arrive, but they will be invisible in GA4 reports.

Conclusion

Setting up Events on your site is only a part of understanding the user journey. Although it is a significant part, you still need to understand where users are landing on your site, what activities they are performing, and what you can do to improve all facets. By creating custom events, you can finally answer important questions about your website: which landing pages are generating leads, and which pages are getting the most traffic but users are not converting. All of these are important questions, and creating events helps you with them.

Events tell you what people did on your site; UTM parameters tell you where the users are coming from to your site. Put both of these together, and you have a structure for understanding user attribution: identifying which Platforms are driving the most conversions on the site and connecting them to your marketing spend against actual revenue. We have covered everything related to it in our marketing attribution guide.

One final thing: remember never to send or store users’ personal information to GA4 using GTM, as it violates Google’s policy. If you need help with GTM, GA4, or setting up events, or if you have any questions, reach out to our team. We would be more than happy to assist you with it.