Simply Explained: Sever-Side Tagging

June 2, 2022

                                                        Photo by Jason Goodman on Unsplash

What is Server-Side Tagging?

When you access a webpage (eg. www.mywebsite.com), your browser retrieves the HTML file and additional web components.

Examples of web components:


  • www.mywebsite.com/images/some_banner1.jpg
  • www.mywebsite.com/scripts/some_scripts1.js
  • css.mywebsite.com/primary.css

These are considered first-party because they reside in the same domain (mywebsite.com) as the webpage that you're accessing.


  • www.google-analytics.com/collect
  • www.facebook.com/tr
  • mywebsite.demdex.com/event

On the other hand, these are considered third-party because they reside in external domains.

Because they are third-party components, they can be subjected to browser tracking prevention and ad blockers. Which means data may be blocked from going to the endpoints, this may cause inaccurate insights.

With server-side tagging, what we're trying to do is turn some of these third-party components into first party by introducing an intermediary server that resides in the first-party domain (eg. sst.mywebsite.com).

The Benefits of Implementing Server-Side Tagging

There are many benefits of implementing server-side tagging, including improved security and having control over the data that is sent to the endpoints. I recommend checking out more examples by Simo Ahava.

For this article, we want to focus on how server-side tagging can improve tracking that is powered by third parties, like the diagram example above.

In our previous articles (#1, #2), we showed the impact of Apple's Intelligent Tracking Prevention (ITP), specifically how it greatly limits the lifespan of cookies initiated by third-parties scripts on:

  • Safari browsers on all operating systems (desktop and mobile)
  • All browsers on iOS

For analytics, this has the effect of NOT being able to identify returning users who come back to your website after 7 days. That's why we see the increasing New Users metric in the previous articles. In fact, we're seeing close to 100% New Users for the affected browsers.

In mid-Feb 2022, we helped a client implement server-side tagging, and we observed quite a dramatic improvement in tracking, seeing the New Users metric going back to normal.

This one example shows how Sever-Side Tagging can help you take back (more) control of your data.

Sparkline aims to provide data accuracy, comprehension and consolidation, and most importantly, tangible insights for businesses. Get in touch if you’d like to find out more about server-side tagging.