Server-side tracking: definition, benefits and implementation
Updated on February 22, 2026
Quick definition
Server-side tracking is a method of collecting analytics data in which navigation events and conversions are sent from the publisher's servers to analytics and marketing platforms, rather than from the user's browser. It offers resilience to ad blockers, independence from third-party cookies and greater control over the data transmitted.
How it works
In traditional client-side tracking, JavaScript scripts are loaded in the browser and send data directly to analytics platform servers. This approach has several vulnerabilities:
- Ad blockers block requests to known advertising domains (up to 30–40% of traffic on some sites)
- Safari's ITP restrictions limit cookie lifespan to 7 days
- Site performance is degraded by loading many third-party scripts
In server-side tracking, an intermediary server (GTM Server-Side, Node.js, Go) receives events from the browser, processes them and forwards them to the platforms. The benefits:
- Requests go out from a first-party domain (tracking.mysite.com), invisible to ad blockers
- The publisher controls exactly which data is transmitted to each partner
- Cookies can be set as first-party data with a full lifespan even on Safari
- Site performance improves by reducing client-side scripts
However, implementation requires dedicated server infrastructure and more advanced technical skills.
Why it matters
Server-side tracking has become essential to maintain the quality of analytics data in an environment increasingly hostile to client-side scripts.
With the proliferation of ad blockers (estimated at 30–40% of web users in France), browser cookie restrictions and GDPR requirements, client-side tracking alone is no longer sufficient for a reliable view of traffic and conversions.
How to improve or use it
- 1Start with GTM Server-Side (the most accessible solution), deploy a container on Google Cloud Run or a dedicated instance.
- 2Redirect client calls to your own tracking domain.
- 3Progressively migrate your most critical tags (advertising conversion, analytics) to the server.
- 4Verify that collected data is identical before disabling client-side tags.
- 5Document the data transmitted to each partner for the GDPR register.
With Sublim
Sublim is natively architected as server-side: analytics events are sent directly from your site to Sublim servers hosted in Europe, without going through a heavy client-side script susceptible to being blocked by an ad blocker. This approach guarantees complete data collection, minimal latency and native GDPR compliance — unlike Google Analytics' classic client-side tracking.
Frequently asked questions
Does server-side tracking completely eliminate client-side scripts?
No, server-side tracking generally requires a minimal client script to capture browser events (clicks, scrolls, navigation). This light script sends the data to your intermediary tracking server, which then redistributes it to the analytics platforms. The difference is that the requests come from your domain rather than from identifiable third-party domains.
Is server-side tracking suitable for small organisations?
Setting up server-side tracking requires DevOps skills and infrastructure costs (GTM container hosting, maintenance). For small organisations, natively non-blockable analytics solutions like Sublim provide the same data-reliability benefits without the complexity of a full server-side infrastructure.
Does server-side tracking improve GDPR compliance?
Yes, server-side tracking gives the publisher full control over data before it is transmitted to partners. It allows sensitive personal data (full IP, non-consented demographic data) to be removed before sending, lets you transmit only the data for which consent has been obtained, and lets you precisely document data flows for the GDPR register.
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