Table of contents for how to set up GA4 via GTM server side tagging  

1. Working of a Facebook tag through the server-side container
2. Configuration of the client-side GTM container
3. Updating general parameters
4. Updating user data parameters
5. Updating custom data parameters
6. Configuring server-side GA4 tag (exclusion of Facebook parameters)
7. Configuring the Facebook Conversion API Tag
8. Preview and debug
9. FAQ

In this article, I will talk about GTM server side tagging for Facebook.

Note: This article is related to the server-side tagging articles below. If you haven’t read the earlier ones, I would highly recommend going through them. You can find them here:

1. How to create a server-side container for Google Tag Manager
2. How to configure DNS for a GTM server-side container
3. How to send data from a website to a server-side container
4. How to set up GA4 via GTM server-side tagging

Now let’s get back to our main article topic of setting Facebook tags via a server-side container. We will first learn more about how it works, and then we will do the actual implementation.

Working of a Facebook tag through the server-side container

I have tried to explain the working of the server-side Facebook tag through the below image and steps.

Step-1: When the user interacts with the website a server request is made, and at the same time, the GA4 web tag fires on the client-side GTM container.

Step-2: This GA4 web tag then transports the data captured from the website (events, pageviews, variables) and passes it to the GA4 web client in the server-side container. 

Step-3: Now the GA4 web client request is processed in the server-side container and the related parameters are passed to the individual third-party server tags like Google Analytics 4 and Facebook.

Step-4: Once the required parameter is received in the Facebook Conversion API Tag, the data is finally dispatched to the Facebook server.

Now that you know how the Facebook tag works on the server-side container, let’s jump to configure it.

Configuration of the client-side GTM container

You need to configure the client-side GTM container to send values from the website to the GA4 client in the server-side container. 

This is done by using the ‘transport_url’ field. I have explained this in great detail here: How to send data from a website to a server-side container. 

Since in this article we will talk about setting up the Facebook Conversion API tag using the basic GA4 tag we will focus on the additional data parameters setup, as below. 

Updating general parameters

There are many data parameters that you may want to send to Facebook, e.g. ‘Event Name’, ‘Page location’, ‘Event ID’ ‘Ecommerce variables’, etc. We will configure those parameters first.

Note: I am assuming you have already created the required event tags, triggers, and variables in the client-side GTM container. 

If you need more information about how to create variables and use them you can find them here.

• How to set up GA4 Custom Events via Google Tag Manager
• Google Tag Manager Variables and Triggers Tutorial

As an example, I am going to configure the purchase event which we will send to Facebook

Follow the below steps, to begin with:

Step-1: Navigate to the GTM client-side container and click on ‘Tags’.

Step-2: Now click on ‘Purchase event’.

Step-3: As you can see from the below image, I have already configured the purchase event and it is being sent to the server-side container. Now, let’s add a general parameter like ‘Page location’ to this event. 

Step-4: Under ‘Event parameters’ click on ‘Add Row’.

 Step-5: Now type ‘page_location’ under parameter name and click on the + button beside the value text box.

Step-6: Now select the variable ‘Page URL’.

That’s it, you are done! Just like we added the ‘page_location’ parameter you can also add similar other parameters like:

• Event_ID: If you want to identify each event uniquely.
• Action_Source: Like website, application.
• Campaign_Details: If you are tracking any campaigns.
• Any other parameters which are useful to your organization that you would like to add.

Updating user data parameters

Along with general parameters, you may also like to pass a few user-related parameters to Facebook like ‘User Email Address’, ‘User City’, ‘User Phone Number’, etc. 

You may be thinking that this is PII (personally identifiable information) so how can we pass this in the GA4 tag. But hold on, we will just pass it to our server-side container and not to GA4 directly. We will filter out such variables in later steps. 

Step-7: To add user-related data parameters, click on ‘User Properties’ and then click on ‘Add Row’.

Step-8: Now type the parameter field you want to add. As an example, I am adding ‘user_data.email_address’ and then click on the + button to select the variable.

Step-9: Select the ‘User email’ variable from the list.

And that’s it. Similarly you can also add following user related variables.

• user_data.phone_number
• user_data.address.first_name
• user_data.address.last_name
• user_data.address.city
• user_data.address.region
• user_data.address.postal_code
• user_data.address.country

Your final configuration may look like below

Updating custom data parameters

Along with general parameters and user-related parameters, you can also pass custom data parameters such as ‘transaction_id’ ‘value’, ‘currency’, ‘ecommerce variables’, etc. 

You can also pass facebook specific parameters like 

• x-fb-ud-ge: Hashed user gender
• x-fb-ud-db: Hashed user date of birth
• x-fb-ud-external_id: External ID, e.g. advertiser loyalty ID with recommended hashing
• x-fb-ud-subscription_id: Subscription ID, no hashing needed
• x-fb-ck-fbp: Facebook cookies

Once you have added all the required parameters, the configuration at the client-side GTM container is done and you can save the tag.

Configuring server-side GA4 Tag (exclusion of Facebook parameters)

Now since we do not want to pass any PII data to the GA4 account, we need to exclude it from the GA4 tag in the server-side container. 

Follow the below steps to know more:

Step-1: Navigate to your server-side container and click on ‘Tags’ and then click on the GA4 configuration tag.

Step-2: In the tag configuration, click on ‘Events Parameters’ and then click on ‘Add Row’ under ‘Parameters to Exclude’.

Step-3: Now add all parameters that contain user-related PII data, Facebook-specific parameters.

Note: If you don’t remember which parameters to exclude, you can simply put the server-side container in preview mode and generate a specific event. You will get all the information about the parameter name which needs to be excluded like in the below image.

Step-4: Save the tag and you are done with configuring the GA4 server-side tag.

Configuring the Facebook Conversion API Tag

Now let’s set up the actual Facebook server-side tag. But, before you proceed to the set up, let me tell you the requirements for this.

We will be using the Facebook Conversion API Tag template here and we will need the below parameters.

1. Facebook Pixel ID: To which we will send data. You can get this at https://www.facebook.com/events_manager
2. API Access Token: So that we can interact with the API.
   Read more about API Access Token here: https://developers.facebook.com/docs/marketing-api/conversions-api/get-started#access-token
3. Test Event Code: Optional

Follow the below steps to continue.

Step-1: Navigate to your server-side container and click on ‘Templates’.

Step-2: Click on ‘Search Gallery’ under ‘Tag Templates’.

Step-3: Select ‘Facebook Conversion API Tag’ and add it to a workspace.

Step-4: Now Navigate to the ‘Tags’ tab and click on ‘New’.

Step-5: Give your tag a name like ‘Facebook Conversions API Tag’ and click on ‘Tag Configuration’.

Step-6: Now select the tag type as ‘Facebook Conversions API Tag’.

Step-7: Now add your Facebook Pixel ID and API Access Token code, You can type ‘Test1234’ in the ‘Test Event Code’ and select ‘Action Source’ as a website.

Step-8: Click on ‘Triggering’ to create a trigger for our tag.

Step-9: Now apply the below configuration to your trigger:

• Trigger fires on ‘Some events’
• Condition: Client Name ‘equals’ GA4.

Step-10: Save the tag and you are done.

Preview and debug

Follow the below steps to preview and debug.

Step-1: Navigate to the server-side GTM container and click on ‘Preview’.

Step-2: A new window will open like below with a blank summary.

Step-3: Go to your website and perform the purchase event. Once you do that, you should be able to see the purchase event is fired like in the below image and the Facebook Conversion API Tag has also fired.

Step-4:  Now click on the ‘Request’ tab and you should see the outgoing ‘HTTPS’ request to ‘https://graph.facebook.com/) with status code ‘200’.

If you click on the ‘Post-200’ status code you will get more details like below

Now navigate to the Facebook Event testing tool and click on ‘Test Events’. You should be able to see the purchase event just like below

Congratulations! You have successfully set up the Facebook Conversion API Tag using the server-side GTM container.

Note: Just like this purchase event you can send any event from your website to Facebook using server-side GA4 client and the Facebook Conversion API Tag. Just keep in mind to exclude the PII-related parameters from the GA4 server-side tag and to hash the necessary parameters.

Related Articles:

• How to Create Server Side Container for Google Tag Manager
• GTM Server Side Tagging Tutorial
• How to Configure DNS for GTM Server Side Container
• How to send data from Website to Server Side Container
• How to set up GA4 via GTM Server Side Tagging

Frequently asked questions about GTM server-side tagging for Facebook tutorial