Programmatic advertising has transformed how businesses reach audiences by using automated technology to buy and optimize digital ads. However, tracking the success of any paid digital campaign requires proper setup. This is where Google Tag Manager (GTM) comes into play.
GTM is widely used by digital marketers and businesses. It allows them better manage and deploy tags (ie, tracking pixels or code) across websites without having to directly (and manually) modify the site code. For Programmatic ads, GTM offers two tracking methods: server-side tracking or client-side tracking.
Here, we’ll go into detail about the differences between these two types of tracking, and where they might be useful.
GTM Server-Side Tracking
What is GTM server-side tracking?
Server-side tracking is the process of capturing and sending data from the GTM cloud server instead of the user’s browser. Using this method, the server acts as the middleman, receiving data from the client and processes it before forwarding it to third-party platforms.
How does GTM server-side tracking work?
In server-side tracking, when a user interacts with a website or app, the data is first sent to a web server rather than being collected directly through the user’s browser using JavaScript tags. The server then forwards the data to third-party platforms, such as Meta, Google Analytics, and DSPs.
This bypasses the client’s own browser, which reduces any risk of data being lost or blocked by ad-blockers, browser restrictions, or privacy regulations.
Brands and agencies who run programmatic advertising can find server-side tracking particularly useful, as it provides greater control over data accuracy and privacy.
How to set up GTM server-side tracking
- Create a server container: This can be found in Google Tag Manager, and allows you to set up tags that run on your server, instead of in the user’s browser
- Set up your server: This can be Google Cloud. It will be used to host your tracking data, and is where all the data will be sent before being processed and sent to the required tracking platforms.
- Configure your tags: Any tags that traditionally run in the user’s browser (such as Google Analytics) should be configured to send data to your server container first.
- Deploy the tracking system: Test your programmatic ads to ensure that your tags and tracking are working properly.
Pros of GTM server-side tracking
Data accuracy and reliability
Because data is sent directly to the server, rather than through the user’s browser, there isn’t the risk that information will be blocked or skewed by ad-blockers, browser restrictions, or even connectivity issues.
Enhanced data privacy
Data accuracy and reliability go hand-in-hand with enhanced data privacy. By processing data through a separate server, you’re able to limit the amount of information that’s shared with third-party platforms — which is crucial when keeping compliant with privacy regulations like CCPA and GDPR.
Improved page performance
As well as improving data accuracy, server-side tracking can improve website load times, as tracking isn’t reliant on the user’s browser. This enhances user experience, which is crucial when you want users to make a purchase from your ad.
Customization
Using server-side tracking gives you greater control over how you collect data, depending on your specific needs.
Cons of GTM server-side tracking
Complexity
As server-side tracking is reliant on an independent server — set up by you — it’s more complex to both set up and maintain in comparison to client-side tracking. You need to ensure your server is able to handle the amount of data being processed, and that you have the technical know-how to manage the server and system.
Cost
Alongside the complexity is the cost issues. Your server needs to be monitored constantly — and carefully. This will usually be done by a development team that understands how the server works and what data and information you need to be tracking. This level of maintenance and server management can come at an additional cost to your business.
Latency
As data needs to first go to your server and then your analytics platform, insights can come after a slight delay, which can affect how accurate your reports are.
GTM Client-Side Tracking
What is GTM client-side tracking?
While server-side tracking sends data to an independent server, client-side tracking collects data directly from the user’s browser. This is done using JavaScript, and is the more common way to track user behavior and ad performance.
It’s best suited for companies that don’t have an in-house dev team, and for those that are looking to easily and quickly monitor traffic and events on their site to measure ad success.
How does GTM client-side tracking work?
When using client-side tracking, the user’s — or client’s — browser sends information and data directly to the platform you’re using to track performance, such as Meta or Google Analytics.
This means that whenever a user clicks on a display ad, for example, the JavaScript embedded in the website sends data to your tracking platform, so you can see where your clients are coming from.
This works by adding a GTM container to your website source code, in the head and body. Once added, you can go in and add tracking. The container can hold multiple tags, such as Google Analytics, Meta Pixel, or conversion tracking codes. Then, when a user visits the website, the browser runs the tags within the container.
How to set up client-side tracking
- Create a container: This will be in Google Tag Manager, where all your tracking tags are housed.
- Add tags: These could include Google Analytics, Meta, Pixel, or any other third-party analytics platforms.
- Set up triggers: Triggers should clearly define when tags should be fired, such as when a user comes to your website from a specific ad.
- Publish: Publish your container and start tracking the data as it comes into the analytics platform.
Pros of GTM client-side tracking
Tag management
All tags for your site are stored in one container. This holds all tags, triggers, variables, and any related code that’s used to measure user interactions. Whenever a user visits the site or page, the container loads and triggers all the related tags.
Real-time testing
You can use GTM preview mode at any time to make sure that your tags, triggers, variables, and code are all working properly.
Fast deployment
You can access the container anytime to add more tags. These will then be live as soon as they’re published, without the need for additional, complex set up.
No additional hosting costs
Unlike server-side tracking, you don’t need to pay extra to host a server. Everything is hosted in the Google Tag Manager’s containers.
Cons of GTM client-side tracking
Data loss
Thanks to things like ad blockers and browser privacy settings on the client’s side, you run the risk of incomplete data collection.
Limited control over data privacy
All data is sent directly to third-party platforms, giving you less control over what data is shared.
Page performance issues
Tracking scripts can sometimes delay page load times, especially if the user is using a mobile device. This leads to a poor user experience, which can affect conversion rate.
Setting Up Tracking With Grapeseed
Whether you’re looking for client-side or server-side tracking, Grapeseed Media is here to help. We’re specialists in implementing and tracking programmatic ads, and work closely with you to optimize campaigns to drive results.
We can guide you every step of the way if you’re unsure of the world of programmatic. Get in touch with our team to find out how programmatic can work for your business, and start tracking your ads now.