What is the Google Tag? To install GA4, should I install the Google Tag ID, the Measurement ID, or both? Should I use one Google Tag for all my Google products, or install separate ones for Google Analytics 4 and Google Ads?? Where can I find my tag ID? What exactly does it mean to combine them?

If Google tags puzzle you, you’ll find your answers simplified here. 

The GA4 Google Tag replaces the GA4 Configuration Tag, serving as a vital piece of code required for installing Google Analytics 4 on a website. It’s essential for using Google Products like GA4 or Google Ads. The tag must recognize your GA4 web data stream (your app or website) through an identifier, enabling it to send data from your site to GA4.

If it’s still unclear, we’ll provide examples to help you better understand how everything works. 

What Is Google Tag in GA4?

The Google Tag in GA4 is a JavaScript library. It is a code whose job is to make it easier for website owners to use Google services like Google Analytics (GA4) and Google Ads.

You can view the Google Tag as a connector that links your website with Google’s various tools like Google Analytics. These tools, known as Destinations, each come with their unique ID.

For GA4 to collect data from your website, it needs to work with the Google Tag. Once connected, the Google Tag sends your website’s data to GA4 for analysis.

Google Tag Examples 

Ga4 Google Tag Example

What’s an example of a Google tag? Let’s look at one. 

When you create a new property in GA4, it automatically comes with two tags:

  • A Google Tag ID
  • A Measurement ID

The Google Tag ID is recognized by the prefix GT. For example GT-123456

The Measurement ID for GA4 is recognized by the prefix G. For example: G-123456

Example of a Google tag renamed xyz-company for a newly created property:

Example of one Google tag sending data to two GA4 Properties, or two websites (more about this in the upcoming sections): 

Example of the Google tag for a Google Adwords destination:

Is There More Than One Google Tag?

The term Google tag can create confusion as it refers to both gtag.js and the specific configurations within that framework for various Google services.

For instance, Google’s documentation uses the term “Google tag” not only for the single tag that connects to other products (such as GA4, Google Ads, etc.) but also for other product IDs.

To clear the confusion, just remember that there’s only one Google tag in the sense of the gtag.js framework, but within this framework, there are multiple “Google tags” configured for different services, each with unique IDs like G-XXXXXX for GA4, AW-XXXXXX for Google Ads, and so on.

Even your Google Tag Manager container ID is called a Google Tag.

How Does Google Tag Work?

As mentioned, the Google tag is a single code sending data to Google products like Google Analytics. 

The Google Tag uses destination IDs to get specific settings for each destination (GA4, Google Ads, etc.) and to send events to the right place.

You can use one Google Tag on your website and let it send data to multiple destinations instead of multiple tags for different Google product accounts. 

As described by Google, other benefits include: 

  • New capabilities and adopt new features without having to code 
  • Minimize the need to make code changes to your site.
  • Manage access: You can also now manage user access to your tag settings separately from access to your other products, giving you more control over who has access to change your critical measurement settings.

When it comes to standard installation and management of Google products such as GA4 and Google Ads, the process remains largely unchanged unless you combine your tags or add a destination.

Let’s explore some practical examples of this.

Adding A Destination to a Single Google Tag 

On the surface, how you manage your property and tracking won’t change much. In many cases, you can be fine with this setup, meaning you create your GA4 property, add the measurement ID in the Google Tag template (follow our installation guide in this post) and that’s it. 

However, the benefits of the Google tag become evident when you combine tags or add a destination to one single Google Tag. 

If you’re an Administrator, you can add or remove destinations on your tag. By adding destinations to your Google tag, you can avoid extra tagging on your site and keep using the same settings your tag already has. 

For instance, if you’re working with an agency that used to send data to one of your product accounts using their own Google tag, you may add that destination to your Google tag instead.

Follow this simple guide on how to add a destination to a Google tag.

This is how the migration looks before saving it.

Now, we have one Google tag (GT-MK9QVCTK) sending data to two websites (GA4 properties): 

  • G-RN428PYYST (for website 1)
  • G-ZLG72M74HV (for website 2)

When you use GTM’s Preview mode to visit website 2 the one connected to Google Analytics G-ZLG72M74HV in our example), GTM will operate the same, focusing on that website.

However, if you click on the Google Tag ID next to the GTM ID, you’ll notice two Page View hits sent to the two destinations we mentioned earlier. 

To illustrate further, we’ve created a generate_lead event. When testing this event for a specific website, despite using one Google Tag for both properties (two websites), the generate_lead event is sent only once.

This contrasts the other hits like Page View, and User Engagement that appear twice since the Google Tag Configuration settings apply to two websites. 

If events from properties with the same Google tag aren’t shared, what is shared then?

Your Google Tag configuration settings. 

To find these settings, go to Admin → Data collection and modification → Data streams

In the Google Tag section, click Configure tag settings

Go to the Settings section at the bottom.

To give you a quick idea of what these settings can do, click Manage automatic event detection

If you’re familiar with GA4, this will remind you of Enhanced Measurement

For instance, if you turn off Form interactions here, this adjustment will apply across all destinations connected to your Google tag, overriding any activated settings for the same feature within their Enhanced Measurement options. Simply put, Form interactions even when enabled in your other properties won’t work. 

The question is: should you combine your tags or add a destination? 

We believe it’s currently best to keep them separate, and later combine tags or add destinations as needed. This approach helps prevent sharing settings you wouldn’t want with other destinations, such as Google Ads.

How Do I Create a Google Tag?

In the GA4 context, setting up a Google tag is easy and happens automatically. All you need to do is create a property.

From your GA4 account, simply scroll to the bottom of the page and click on Admin.  

  1. Click the + Create button  
  2. Click Property

Next, follow the steps to create your property.

Once finished, you’ll be directed to the page containing your Web Stream Details.

If you already have a property, you can access it this way:

  1. Click Admin 
  2. In Data collection and modification, click Data Streams
  3. Click your Data stream

In the Google Tag section at the bottom, click Configure tag settings

Notice that your Google Tag has two ID’s:

GT-K58QZGQ4: the actual Google Tag ID. This tag sends data to a destination, in our case GA4.

G-ZLG72M74HV: your GA4 google tag ID. This is the same as your Measurement ID in the previous image. 

Where Should I Put the Google Tag?

For Google’s measurement products like GA4 to work properly, you’ll have to install the Google tag on all pages of your websites. 

Some ways to install your tag include: 

  1. Using your website builder or CMS (like Wix or WordPress)
  2. Install manually
  3. Using Google Tag Manager

We’ll see how to install the tag using Google Tag Manager and the GA4 Google tag template. 

To illustrate why this is necessary, refer to the question mark from the previous section. 

Hovering over it will display a message box:

This tag has never been detected.”

Also, in GTM, if you try to set up a GA4 event without first installing the Google Tag, you’ll receive the following message:

⚠️No Google tag found in this container.

This indicates that we need to install the Google Tag on our website. Once this is completed, the same question mark will turn green.

How To Setup The Ga4 Google Tag In Tag Manager 

In GTM, create a new tag: 

  1. In the menu, click Tags
  2. Click New

  1. Click the Tag Configuration box
  2. Select Google Tag

In the Tag ID field, paste your Google Tag ID. 

Since we’re interested in using GA4, we’ll use the GA4 Tag ID. 

Remember this is the same as our GA4 Measurement ID. 

To get your measurement ID, go to Admin → Data collection and modification → Data streams

Copy and paste it into your Tag ID field, in your Google Tag Configuration in GTM.

Testing Your Google Tag

Use GTM’s Preview mode and add your website link. 

Your Tag should be firing. 

In addition, the green question mark we saw previously in GA4’s Configure Tag Settings should turn green. 

Note: the question mark not turning green doesn’t always indicate that events aren’t being sent to your property. This could happen if you entered your website domain incorrectly when creating your web data stream.

When you create a GA4 event, Tag Manager will acknowledge that a Google Tag is present in your container, as indicated by a green checkmark.

What Is the Difference Between Google Tag and GA4 Tag?

A GA4 tag is a code snippet for tracking website actions, such as clicks and purchases. o deploy GA4 tags, you typically need access to your website or app code, or you can use a tag management system like Google Tag Manager for easier deployment.

In contrast, the Google Tag enables the activation of various measurement products and features from Google, including Google Analytics 4.


We’ve thoroughly explored the Google tag’s function within Google Analytics 4, using multiple examples in GA4 and Google Tag Manager.

The Google tag is one piece of code that allows you to measure your website and ads performance. We’ve covered the benefits of this tag and how to use it to install GA4, and add other products with their own tag or to add them to one single tag.

While there’s only one Google tag framework, the associated IDs (e.g., G-XXXXXX, AW-XXXXXX, DC-XXXXXX) represent different product configurations within it. Together, these configurations are referred to as “Google tags.”

Hopefully, this post clarifies how Google tags work and how they can benefit your website’s performance.

Let us know how you use the Google Tag.