How PRO Marketers Use GA4 Custom Dimensions To Get Desired Insights

Brian Bojan Dordevic
About The Author

Brian Decoded

President at Alpha Efficiency

Join me at the forefront of web design and digital marketing innovation. I am obsessed with web design, business philosophy and marketing performance.
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Is your boss complaining that your Google Analytics 4 reports feel empty? Like the crucial piece of information is always missing… You constantly fail to collect the data you want… Others keep swearing by GA4 custom dimensions and how they can help you gain insights like never before. But whenever you try using custom dimensions in GA4, things just get more confusing.

It feels like shooting in the dark while your business slowly falls behind the competition. Even your colleagues start to think you’re incompetent for the role. Something has to change quickly. Or you’ll never get that pay raise. You’re tired of watching other marketers earn big while you’re stuck on $60k per year.

None of that is your fault…

I was also shocked to find out that Google Analytics 4 custom dimensions were drastically different than in Universal Analytics. I was confused and thought I’d never catch up with the changes. But it all became super simple once I realized how concepts have changed with this new platform. The problem wasn’t lying in GA4 custom dimensions and other shiny features – but in my perspective.

Soon, I could decode user behavior on my website in a way I hadn’t experienced before. The possibilities were exhilarating.

And the results? My digital marketing agency started collecting much deeper insights into user interactions. We knew exactly how to take our marketing strategies to new heights – for both our website and our clients. And let me tell you – clients LOVE our new reporting setup enriched with custom dimensions.

Anybody can become good at GA4 and web analytics. Today, I’ll help you experience this transformation.

You’ll learn how to use GA4 custom dimensions to give your firm a competitive advantage and boost marketing campaigns like an expert. Your boss will love you. And you’ll gain confidence in your skills.

Whether you’ve just heard of these or want to know how to use custom dimensions to the fullest potential, keep reading. I’ll help you understand this feature better, explain what has changed since UA, and show you some cool benefits. Finally, you’ll learn a simple way to set up custom dimensions.

Table of Contents:
GA4 custom dimensions guide.

Let’s First Explain What GA4 Custom Dimensions Are

If you’re unfamiliar with custom dimensions and didn’t use them in Universal Analytics, don’t worry. It’s not exactly rocket science.

With enough practice, anybody can set up GA4 custom dimensions like a pro. Even if you’ve just recently landed this marketing assistant role.

In this section, I’ll explain this powerful feature and give you some practical examples. But even if you’re already using GA4 custom dimensions, it’s always a good idea to refresh your knowledge, right? I’ll first help you understand what dimensions essentially are, and then we’ll move on to explaining custom dimensions.

I know all of this can be difficult to understand at first. When I first heard of all these web analytics terms, I felt it was impossible to master them all. What helped me the most were practical examples and thinking about how GA dimensions work in real-life situations and how I can use them for my business. , So you’ll find many examples in this article. You have my word on that.

Let’s keep moving.

Understanding the term ‘Dimensions’

Let’s start with the basics – dimensions (I want you to forget about custom ones for a moment). Think of dimensions as characteristics or attributes of data. They could describe an event, a product, a user, or a website. Simply put, they help us understand the ‘what,’ ‘where,’ and ‘when’ of events.

I know this can sound confusing at first, so let me give you an example:

Let’s say a user signs up for your SaaS platform. You might be interested in several dimensions of this event, such as:

  • The signup method – did they create an account using an email address, or did they sign up using their Facebook or Google account?
  • Or maybe, you’d want to know their geographical location
  • Or the specific browser they used.

Stop thinking of dimensions as your enemy. They’re your friend. All these attributes help you understand user behavior in depth.

Google Analytics 4 Custom Dimensions Explained With Examples

Noticing that Google Analytics 4 has no default dimension for every attribute you’re interested in is initially scary. How can you collect the data your team wants?

As every business has unique needs, it would be impossible to have in-built dimensions that suit everyone. For example, you won’t find any dimensions specifically related to SaaS businesses. This is because most businesses that use GA4 aren’t selling SaaS products. Luckily, custom dimensions in GA4 can help you get any insights you want.

Let’s say you notice that users who sign up via Facebook tend to churn less than users who sign up with Google.

You might hypothesize that it has something to do with the age of the users, but GA4 doesn’t provide that information by default.

Here’s where you can create a custom dimension to start tracking the age of your users when they sign up. Let’s call it ‘Signup Age.’

As you can see, using custom dimensions in GA4 allows you to create your unique data parameters. You name them, define what they should track, and Google Analytics 4 does the rest. This data will give you insights uniquely suited to your business model and goals. Possibilities become endless.

Now, here’s where things get somewhat complex (don’t worry, it’s not that bad). In GA4, there are currently three scopes of custom dimensions, but this might change in the future):

  • Event
  • User
  • Item

Before you start to panic, let’s explain each.

Event-scoped custom dimensions in GA4

In Google Analytics 4, almost every interaction, such as a page view, button click, or form submission, is treated as an event. But if you want to gain context or learn additional information about these events, using event-scoped GA4 custom dimensions is the solution. This will help you understand details like the value of the event or whether the intended action was completed successfully.

Sounds complicated? Let’s put it in perspective with a practical example:

Suppose you operate an e-Commerce business. The crucial event on your website is a product purchase. With event-scoped custom dimensions, you could track additional attributes for each purchase, such as ‘Coupon Code Used,’ ‘Delivery Option Chosen,’ or even ‘Gift Wrap Selected.’ Each of these dimensions can provide valuable insights. For instance, you might find that certain coupon codes lead to higher-value purchases or that users who choose expedited delivery are more likely to buy again.

Remember, event-scoped custom dimensions only apply to the particular event with which they’re associated. So in our example, the ‘Coupon Code Used’ would only be tied to the specific purchase event and not any other interaction the user might have on your website.

User-scoped custom dimensions

As the name suggests, user-scoped custom dimensions in GA4 are all about understanding the characteristics of your website or app users. They’re a powerful way to analyze attributes tied to users that persist beyond a single event or session. This means that once you set a user property for a particular visitor, it gets associated with all the events the user generates going forward.

You might be wondering, “How does this work?” Let’s illustrate this with an example.

If you’ve created a language learning app, you’d want to track which language each user is learning. When a user chooses a language, you could set a user-scoped custom dimension, say ‘Learning Language,’ and assign it the value of the chosen language, such as ‘Spanish’ or ‘French.’ Now, whenever that user interacts with your app, you’ll know which language they’re learning.

How can this “Learning Language” custom dimension help you?

By allowing you to spot trends and patterns within user behavior. You might find that users learning Spanish spend more time in the app or that users learning French are more likely to purchase additional materials.

This can be a great addition to your custom reports. You might then suggest investing additional money in ads targeting French learners (hoping to monetize on additional materials) or Spanish learners (if your company prioritizes building an active community).

Custom dimensions, including the ability to create a user-scoped custom dimension, can significantly empower your whole business strategy. By leveraging custom dimensions and metrics within a GA4 property, you gain deeper insights into user behavior and preferences, enabling more targeted and effective decision-making.

Item-scoped custom dimensions

If you’re selling products within your website, you’ll love item-scoped custom dimensions.

These were a newer addition to GA4’s powerful analytics capabilities, further broadening the scope of data you can collect and analyze. Item-scoped dimensions target the specific products or services sold on your online store, providing deeper insights into their attributes.

I’ll illustrate this on the e-Commerce website selling clothes example:

Suppose your company introduces a new line of eco-friendly t-shirts in its online store. Each of these t-shirts has unique attributes like color, size, and material (like 100% organic cotton). You could set up item-scoped custom dimensions for these attributes. This way, you can track not just how many t-shirts were sold but also granular details like which color or size was most popular or if t-shirts of a particular material saw more returns. 

What Has Changed Since Universal Analytics?

The shift from Universal Analytics to Google Analytics 4 (GA4) has meant some noteworthy changes. And custom dimensions were no exception. Let’s dive into what these changes mean for you and your business.

Universal Analytics custom dimensions were neatly divided into four scopes:

  • User
  • Session
  • Hit
  • Product

When GA4 was first launched, only User and Event scopes were available for custom dimensions.

If you’re in charge of marketing for an online clothing store and used to track ‘Product Category’ under the Product scope in Universal Analytics, you were probably disappointed. The product scope was no longer there. You might have been left wondering how to continue tracking such key product-level information. However, Google understood these user needs and recently introduced Item scope to GA4.

Another change is that once you set a user-scoped custom dimension, it will not apply retroactively to past events. It also won’t change any data from the same session before the user property was set. This is because Google Analytics 4 is moving away from the concept of sessions and focusing more on events and users.

Perhaps one of the most welcome changes is the increase in the number of allowed user-scoped custom dimensions. Where Universal Analytics allowed up to 20 custom dimensions in its free version, GA4 has upped the ante by allowing up to 25 user-scoped custom dimensions per property. I’ll explain GA4 custom dimension limits in more detail later in this article.

For now, let’s say that GA4 gives you more control and richer insights into your users’ behavior. Although GA4 may feel like a major shift if you’re used to Universal Analytics, understanding and adapting to these changes is more than worth it.

Reasons why you should use custom dimensions in Google Analytics 4.

4 Reasons Why You’ll Love Using Custom Dimensions in GA4

My web design agency in Chicago has clients from various industries and with various needs. Using predefined dimensions in Google Analytics simply doesn’t cut it for us. My web analysts heavily rely on GA4 custom dimensions to gather the best possible insights and empower marketing decisions. It takes some time to set these up according to your needs. But once the data starts kicking in, only then you realize how much you were missing out on.

Here’s why I LOVE to use custom dimensions in GA4, and you will too:

They Help You Collect the Exact Data You Need and Create Insightful Reports

Predefined dimensions aren’t enough for me to gather all the data and specific insights into user behavior. They simply don’t cut it for my website and our clients. If I only stuck to predefined dimensions, I’d have a difficult time creating reports that actually make sense.

Custom dimensions come as a lifesaver here. They enrich your reports and provide valuable context. They show you not just what’s happening on your site but why it’s happening and how you can make it better.

But keep in mind that the emphasis is always on action. Insights from your GA4 custom reports won’t mean much unless you act on them. So before reporting to your team or clients, make sure to make sense of data and understand the story it’s telling you.

Advanced Segmentations Make Your Marketing Efforts More Precise

Are you spending your hard-earned budget, yet the results are far from satisfactory? You have a general idea of who your target audience is and even have performed some basic segmentation.

Did you know that creating custom dimensions in GA4 can give you that laser-like precision you need in order to take your marketing efforts to the next level?

Say you’re running a SaaS business. By setting up a custom dimension that tracks the ‘feature usage’ within your app, you can now segment your users based on how frequently they’re using specific features. This can reveal whether they are power users, casual users, or perhaps even struggling with some functionalities. Using UX research tools in combination with GA4 custom dimensions will help you learn even more about user behavior.

You can now craft personalized campaigns addressing the exact needs of each segment. Your users will feel like you totally understand their needs and struggles. Audience members will feel like you’re talking directly to them as individuals. There are not many better ways to strengthen their loyalty and boost customer lifetime value.

You Start Noticing New Patterns During Your Analysis

Making sense of your website visitor’s data can often feel like solving a puzzle with missing pieces. Your GA4 analytics setup is churning out heaps of data, but you just can’t spot any actionable patterns. Frustrating, I know… This used to make me feel like I’d never be good enough at web analytics.

But custom dimensions in GA4 can turn the tables in your favor.

Consider this – your website offers a blog section, a forum, a products section, and a help center. By implementing a custom dimension that tracks ‘Section Engagement,’ you can observe patterns of how visitors transition between these sections. Are forum users more likely to explore your products? Do blog readers often visit your help center? Suddenly, with this custom dimension in place, you start to see your data in a new light. Patterns begin to emerge, painting a clearer picture of your website’s user journey.

Armed with these insights, you can make data-driven decisions to enhance your website experience and better guide your visitors toward desired outcomes.

But you should also keep track of when and why certain actions were taken. I recommend using annotations in GA4 for such purposes. This allows you to put everything in context more easily, highlighting the reasons behind peaks or drops in your data. Soon, you’ll be able to decode the story your data is telling.

GA4 Custom Dimensions Help You FIND What Really Works For Your Company

The online arena has never been more competitive. And it evolves like crazy. You still feel a step behind even when things go in the desired direction.

You keep quiet at team meetings. Without any idea what to do next. All the decisions your team makes feel weak.

Yet, your competitors are CRUSHING it…

They’re driving their dream cars, and people can’t stop talking about their products.

But how is this possible?

Why don’t the same tactics work for you? Isn’t that a bit unfair?

Here’s the big secret:

Even the best marketers out there CAN’T immediately be 100% sure which channel will be most profitable. It’s the game of gathering insights, testing different strategies, and sticking to what works. You only see the end results when you look at successful businesses. Victories get the spotlight, and failures stay hidden behind the curtain.

Remember, what works for one business, won’t necessarily work for another. And what worked yesterday won’t necessarily work today or tomorrow.

GA4 custom dimensions allow you to effectively track the performance of your various marketing channels. You’re able to see how your website visitors interact with each channel and which one leads to the highest conversion rates. For example, eCommerce businesses might find out that their blog content is driving substantial traffic but falls short in generating sales. You can then perform GA4 Google Ads integration to see what specific audiences expect once they visit your pages. If you realize that embedded YouTube videos are closing deals effectively, invest money there. Compounding these small victories will do wonders over time and separate you from the rest.

Custom dimensions offer you the clarity you need in the ever-evolving digital landscape. There are many other Google Analytics 4 benefits too, and I’ve covered these in another article. Once you get comfortable with this platform, I’m sure you’ll be able to boost your company’s return on investments.

How to create custom dimensions in Google Analytics 4.

How To Create Custom Dimensions in GA4 (in 4 Simple Steps)

If you’ve found the process of creating custom dimensions in GA4 a bit confusing before, don’t worry. We’ve all faced similar challenges. That’s why I’ve created this guide and filled it with practical examples so you can follow the process more easily.

Here’s all you need to do:

Start By Identifying Which Data You Want To Collect – Define Your Custom Dimensions

The first step in setting up GA4 dimensions is to ask yourself what additional insights you’d like to gain from your website visitors that aren’t readily available from the standard analytics setup.

Take your time with this step. I’ll try to help you with some examples:

Suppose you run an eCommerce site and have a VIP membership program. In this case, you might want to understand how your VIP members behave differently on your site than your non-VIP members. The custom dimension here could be ‘membership_status.’

Or, if you’re a SaaS business with a complex page navigation structure, tracking specific menu link clicks to understand the user journey could be incredibly valuable. In such a case, ‘menu_item_url’ or ‘menu_item_name‘ could be your custom dimensions.

Implement Your Custom Dimension in Google Tag Manager

The second step to configuring custom dimensions in GA4 is to deploy them through Google Tag Manager (GTM). Here’s a more comprehensive breakdown of the process. I’ll be using ‘menu_item_url’ as our custom dimension example:

  1. Activate Link Tracking: First, we need to ensure GTM is equipped to track any clicks on your website links. Navigate to GTM, click on ‘Triggers,’ then ‘New,’ and finally ‘Just Links.’ Creating this trigger activates the capability for GTM to detect link clicks on your website.
  2. Enable Click-related Variables: GTM has several built-in variables ready to record different types of data. To monitor all data related to link clicks, go to ‘Variables’ and then ‘Configure.’ In the ‘Built-in Variables’ section, enable all the click-related variables. This action prepares GTM to collect essential data, such as the URL and text of the clicked link.
  3. Identify Unique Identifiers for Menu Links: Now, you’ll need to identify a unique identifier that distinguishes menu link clicks from other types of link clicks. Refresh GTM’s Preview mode, visit your website, and click on a few menu links. Back in the Preview mode, you’ll observe variables for each link click. Among these variables, look for something consistent and unique to your menu links. Often, the ‘Click Classes’ variable can fulfill this role, containing distinct values for different link types.
  4. Tailor Your Trigger to Menu Link Clicks: After identifying a unique variable for your menu links (e.g., ‘Click Classes’ equals ‘site-nav__link–main’), you’ll want your trigger to fire only for these specific link clicks. Otherwise, you won’t be able to collect the desired data. Go back to the trigger you created in GTM and edit it to include a condition that captures only menu link clicks, as identified by your unique variable.

Create a GA4 Event Tag

Now it’s time to create a Google Analytics 4 event tag. This tag will help you collect the relevant information and send it to Google Analytics 4. Follow these steps:

  1. Navigate to GA4 Event Tag Creation: Within GTM, click on Tags > New > Google Analytics: GA4 Event.
  2. Name Your Event: Within the GA4 Event tag, you’ll find a field to enter the event’s name. It’s important to give it a unique and descriptive name, like ‘menu_click,’ which will make it easy to identify later in GA4. But this name is not strict – “menu_item_click” or simply “menu” would work equally fine.
  3. Add Event Parameters: After you’ve named your event, you’ll want to add specific event parameters. These parameters help you track additional data points related to the event, providing you with richer insights. For instance, we’ll want to track the ‘menu_item_url’ and ‘menu_item_name’ for our ‘menu_click’ event.
  4. Insert Appropriate Variables: Once you’ve defined the parameters, you need to insert the corresponding GTM variables. Variables represent the values of your parameters. Click the Insert Variables button. For ‘menu_item_url’ and ‘menu_item_name’, we’ll use the {{Click URL}} and {{Click Text}} variables, respectively. Both of these are built-in within GTM.
  5. Test Your Configuration: Finally, verify that your configuration is working correctly. I like to do this by refreshing GTM’s Preview mode, then visiting my website and clicking on a couple of menu items. In Preview mode, you should see that your ‘GA4 event tags’ for ‘Menu Link Clicks’ have fired. Your custom dimension is now successfully tracked.
  6. Save Your Tag: If everything works properly, save your tag. You’re now ready to move on to the next step of creating custom dimensions in GA4.

Register GA4 Custom Dimensions So You Can Start Using Them

As you’re tracking user interactions with custom events and parameters, to fully utilize these in GA4, you must register them as custom dimensions. Please note that you can employ only registered custom dimensions in Funnel exploration and Free Form. And after registering GA4 custom dimensions, their report cards become visible in standard reports.

Here’s how you achieve that:

In GA4, the route is Admin > Custom Definitions. Since we’ve sent two custom parameters with our ‘menu_click’ event, we must register both here. You’d click ‘Create Custom Dimensions’ to initiate the process.

The first field you encounter is the parameter name, which is entirely up to you. This name is how the dimension will appear in your reports, so choose something that makes sense at a glance. It could be ‘menu_item_url’ or a more human-readable ‘Menu item URL’ — choose based on what fits your reporting style.

Next, you select the scope. Because our parameters are only applicable to one event, ‘menu_click,’ and not to all events triggered by the same user, we select ‘Event’ for our scope.

The ‘Event parameter’ field requires careful input. It needs to match precisely the name you gave this parameter in GTM. If you named the parameter ‘menu_item_url’ in GTM, ensure you enter it here exactly the same way. If your parameter doesn’t appear in autocomplete, don’t worry. Just input the correct name and save the dimension.

Repeat the same steps for our second parameter, ‘menu_item_name.’

GA4 may take up to 24 hours to start reflecting these custom parameters in your reports. This lag is standard. So don’t worry; everything is perfectly fine with your setup.

Are You Ready To Start Using GA4 Like a Pro?

Do you feel like you’re not using Google Analytics 4 to its fullest potential? The will to learn is there, but you don’t even know where to start…

It’s true. This can prevent you from building a great career in marketing. Even your employment might be endangered if you don’t adapt to the changes GA4 brought. The labor market is brutal.

As a Google Analytics consultant, I can help you gain control again. Whether you need help learning this new platform from scratch or you want to learn best practices to impress your employers – we can achieve it together.

I’ve gone through the trial and error process within Google Analytics myself. But learning the ins and outs of this platform changed how I observe marketing. All the dots finally connected in my head.

I want you to experience the transformative potential of Google Analytics 4 too.

You can schedule a call with me today. It’s completely free. We will then discuss your unique needs, and I’ll give you some actionable tips. If you’re satisfied, we can establish a consulting plan that suits your schedule. I know how busy your calendar can be working as a marketing manager… That’s why we’ll tailor the sessions to your preferences.

It’s time to start using GA4 like a PRO!


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