Data collection regarding user preferences and activities on websites has long mostly occurred in the web browser. This is fundamentally a client-side model of tracking. Most ad models, user login systems, and analytics have relied on a client-side approach for decades.
Server-side tracking moves the demand to the web server. The user’s client still conveys information, but the tracking data like the cookies stay right on a server that either you or a third-party control. There are also server-to-server solutions where your survey relays information to a third party, such as an ad network server.
The server-side approach has greater resilience, especially when tied to individual user login information. Rather than relying on the browser to hopefully convey the needed data, your server always logs activities and specific users to tie information exactly to the person. This kind of tracking does a better job of surviving things like operating system reinstallations, browser changes, and users cleaning cached data. It also makes it easier to tie user consent to the tracking, thus improving compliance with data regulations like Europe’s GDPR. Users benefit from having a more resilient copy of their tracking information, improving account and session stability across logins.
Server-side tracking is the current trend for several good reasons, but it’s not a magical solution. However, changes in user and browser behavior are pushing tracking onto the server. Likewise, data retention and privacy rules make keeping a record more important than ever before. Let’s take a closer look at what server-side tracking is, why it’s important, and what some of the challenges are likely to be.
Why is Server-Side Tracking Important?
The major source of pressure is the increase in limits on cookies and other trackers in browsers. In particular, Safari and Firefox are shortening cookie lifespans and blocking many types of trackers. More importantly, Chrome maintains support for third-party browsers but is trending toward greater restrictions.
Ad blockers are also becoming a dominant force. 45% of surveyed adults have installed an ad blocker, and there are greater concentrations of blockers among users in technical and business domains. Gen Z users are now approaching 50% usage of ad blockers, too.
Notably, major data collectors like Google, Meta, TikTok, LinkedIn, Snapchat, and Microsoft are also moving toward server-side APIs for their platforms. These companies are moving in this direction because client-side solutions lead to too many lost conversions. That hurts sales and makes it harder to run ad networks while rewarding websites for participation.
On the user end, there is less data loss with a server-side tracker. Users don’t have to be fearful that clearing their browser cache will obliterate their logins and sessions, potentially leaving them locked out of personal information. It also makes long-term website usage more enjoyable because users can be more confident about server-side databases than anything that only resides in their browser’s cookie files.
How Does Server-Side Tracking Work?
The basic infrastructure of server-side tracking usually starts with a dedicated subdomain on your website. You might have something like data.yoursitename.com or analytics.yoursitename.com. Whenever the user takes any action, code sends the information to the tracker. For example, a user’s login time would go straight into the tracker along with their page views, specific pages visited, and form submissions.
A huge benefit of this approach is that the server can secure cookie and tracker data. This means hashing email addresses, stripping non-compliant collected data, and validating the collected data. This leaves less stuff sitting around on the user’s computer or phone for hackers to stumble upon and exploit.
You can handle the infrastructure one of two ways. First, you can use the hybrid approach where the user’s browser processes an on-page scripting call and sends information to the tracker. Likewise, you can have the code on the server page directly pass the information along to the tracker without the browser involved. The fully server-side approach has the notable benefit of making man-in-the-middle attacks harder.
Unique IDs, including event IDs, are the data backbone of most such systems. This means that every individual page visit, click, or submission gets an ID that tracks its entire life. You can take advantage of this to follow how events unfold over time. The tradeoff is that it does demand significantly more server infrastructure to support it. You can’t just offload the demands onto the user’s browser.
Another benefit is that tracking has a much longer life. You can track a customer purchase, for example, the whole way through a product’s entire life. If there are service requests or complaints, you can follow the ID chain the whole way back to the initial purchase.
Client-Side vs. Server-Side Tracking
The biggest difference is where the code runs. In a client-side model, the code runs on the user’s browser. A server-side model means the code runs on the host’s hardware. Client-side models are more vulnerable to ad blocking, short cookie lifespans, scripting language limitations, page speed, and data controls.
A huge advantage of server-side tracking is that you control more of the data. Especially if you’ve relied on analytics packages from third parties, it is nice to have everything in your own databases. The downside is that this is more expensive because you have to set up and maintain servers. The alternative is relying on third-party server-side solutions, but that reintroduces some of the concerns that come with depending on third-party client-side packages.
Notably, the browser isn’t completely gone even from heavily server-driven models. If you wish to capture scrolling, clicks, and UI interactions, you still need the browser’s information.
Server-Side Tracking Benefits
The biggest benefit is that conversion data is more resilient and accurate. With cookies that last as long as your storage policy allows, you can keep tabs on user behavior theoretically for decades after a single click. This resilience also leads to better ad performance because bidders are more confident pricing up well-matched users.
Moving client-side code off your web pages also speeds up browser sessions. This is good for the user experience, and it also benefits SEO because search companies penalize slow-loading pages. Data control is easier because you don’t have to worry about exposing API keys, transaction data, or the user’s information.
Server-Side Tracking Tools
The good news is that there are server-side tracking tools, so you don’t have to build your infrastructure from scratch. For example, Zeustrack provides postbacks, conversion APIs, zero-redirect tracking, and built-in filtering. You can integrate your systems with WordPress, Shopify, or even a custom website. Affiliate tracking is also standard.
There are also options from Meta, TikTok, Snapchat, and Google. Many companies offer free trials or some variant of a free container and then paid hosting.
These types of tools are especially useful from a compliance perspective. If you’re concerned about the ePrivacy directive, the GDPR, CIPA, or similar laws, you can be confident that a third-party solution will meet your needs.
How to Get Started with Server-Side Tracking?
First, you want to audit your current tracking. Figure out what the tags, events, and platforms are that are currently in play. You don’t want to accidentally degrade the quality of your tracking while moving to a server-side setup.
Second, identify your priorities. A small shop website, for example, probably needs to focus on purchases. Conversely, a law firm might be more focused on lead tracking, especially tying actions to specific parts of their content funnel. A group website with a paid membership is likely more worried about the user experience and making sure the sign-up and sign-in systems will be bulletproof.
Once you have a sense of your current situation, you can then select an approach. Hybrid and server-side models have their virtues, so know why you’re selecting your specific approach. You can then proceed to choose a platform that supports your needs and your chosen approach.
Hosting configuration is a big deal at this point. There are managed and cloud-based options. Most businesses aren’t going to leap into a fully self-hosted solution, which runs heavy on infrastructure and tech support. Figure out your preferred subdomain structure because you’re going to have to live with it for years to come. Sort out the consent model for your tracking system, too.
You should now have everything in place to commence testing. Use digital copies of older systems and interactions to confirm that you get as close to an action-for-action duplicate as possible for each one. Compare how the old browser-based system compares to the new server-side one. Once everything is duplicated, you are ready to move the system into production.
From there, life is about monitoring. Log events and user accounts to confirm that the system acts as expected. You can consider expanding tracking services once things settle down from the initial effort.
Does Server-Side Tracking Use Cookies?
Yes, server-side tracking still uses cookies. The big difference is that the cookies exist on a server, use unique IDs, and track against user IP addresses and accounts. Browsers can still cap server-side cookie lifespans, and some like Safari have cookie lifetimes as low as 24 hours for decorative features.
Bear in mind that privacy and data retention rules still apply. Consent should still be affirmative, too. If you’re using a user-login system, you may want to tie the consent process to the initial agreement.
Server-Side Tracking Using Google Tag Manager
Google Tag Manager (GTM) is a server container that collects information from your site and forwards it to vendors. Instances run on Google Cloud, and hosting starts at $45/mo, while a container is free. GTM is a good solution for working with multiple parties.
You should think hard about how much data and event logging you need on GTM. Sending only necessary information is a good way to keep hosting costs down.
Server-Side Tracking on WordPress
WordPress does not natively support server-side tracking, but plugins are available, including one for GTM. WooCommerce in particular supports integration. There are also platform-based options from Meta and Google.
Frequently Asked Questions
Is server-side tracking legal?
Yes, server-side cookies and trackers have been around on the internet for years and are fundamentally legal. However, there are legal concerns, particularly when it comes to major privacy rules like the GDPR, CIPA, and ePrivacy. How you collect information and obtain consent dictate how much of your tracking effort is legal. This is one of the big reasons why you see more cookie and data policy consent blocks appearing on websites.
It is best to keep your tracking system as transparent as possible. Log what you track. Explain to users in documentation what the tracking is for and how you use it. In particular, tell users who you share their data with.
What is the best server-side tracking tool?
Your use case is always going to dictate which solution is best for you. The best server-side tracking tool Zeustrack supports features like server-to-server postbacks and has a conversion API with support for Meta, TikTok, Google, and Snapchat systems. Users get unlimited event tracking, built-in filtering, and managed cloud hosting.
Is server-side tracking GDPR compliant?
Server-side tracking can be GDPR-compliant, but that depends heavily on the setup. Consent needs to be clear, and you should always minimize the tracked data by using hashing, filtering, and anonymization. Follow the EU’s limits on hosting and data retention periods strictly, too. Document all of your data flows so you can answer GDPR questions quickly if a regulator has concerns.
When in doubt, err on the side of excessive compliance rather than assume that a server-side system presupposes greater consent. Modern privacy rules center on the user and their data, not the platform or the method. If you deal with third parties, make sure they are also using the best privacy-conscious practices, too.
