Server Side Tracking: Better data, more insights

Crispin Sill

Crispin SillAugust 2025

In brief

  • Up to 400 days cookie lifetime: 1st-party cookies live 13 times longer than 3rd-party cookies

  • Improved conversion tracking: More precise attribution thanks to longer cookie lifetime

  • Performance boost: Less JavaScript reduces loading times and improves SEO rankings.

  • Hidden tracking IDs: Protection against spam hits and competitor insights.

  • Offline data integration: Linking online and offline conversions.

The end of third-party cookies has long been a reality

The numbers speak for themselves: Safari limits third-party cookies to 1-7 days, Firefox blocks them by default. Even if Chrome postpones their complete abolition, data quality is already massively impaired today.

In our test on Unic.com, we found that users accept cookies differently depending on the industry. While B2B websites often achieve over 80% acceptance, e-commerce sites may only achieve 45-60%.

How server-side tracking closes the data gap

The technology: A minimal JavaScript code records user interactions and sends them to its own server. There, the data is processed, enriched and forwarded to marketing platforms in a controlled manner.

The game changer: By using a subdomain (e.g. tracking.yourdomain.com), cookies are set as first-party cookies. These last up to 400 days instead of just a few days.

Additional protection: Tracking IDs and API keys are no longer visible to competitors and spambots, as they are processed on the server side.

Our practical findings: What works

Measurable data improvements

In our three-month comparison test between client-side tracking, Google SST and Jentis, we documented:

  • Session tracking: 18% more user sessions recognised

  • Conversion tracking: 25% more accurate attribution of purchases to campaigns

  • Engagement measurement: 12% higher interaction rates recorded

  • Attribution window: Extended customer journey analysis due to longer cookie lifetime

Unexpected side effects

SEO boost: Reduced JavaScript code improved Core Web Vitals by an average of 15%. This has a positive effect on Google rankings.

Data protection as a competitive advantage: Customers appreciate the increased data control. In B2B discussions, this is increasingly becoming a deciding factor.

Advanced capabilities through server-side tracking

Offline data integration: Telephone orders, in-store sales, or CRM data can be linked to online behaviour for a 360° view of the customer.

Data enrichment: Tracking data can be supplemented with internal information (customer value, product margins) before being passed on to advertising platforms.

Advanced attribution: Web and server data can be combined for more accurate attribution models that go beyond standard solutions.

Cross-device tracking: Improved user recognition through longer cookie lifetimes and server-based identification.

Our proven implementation strategy

Tool selection: Our recommendations from practice

Google Server Side Tag Manager – Ideal for:

  • Existing Google environments

  • Fast implementation (1-2 weeks)

  • Teams with GTM experience

Jentis – Recommended for:

  • Maximum data control and GDPR compliance

  • Server locations in Germany/Switzerland

  • Companies with high data protection requirements

  • Long-term investment in data quality

Stape – Specialises in:

  • Cost-effective Google GTM hosting solutions

  • Additional features such as ad blocker protection

  • Global CDN infrastructure

  • 1.5x cheaper than Google Cloud Platform

Realistic cost-benefit analysis

Investment costs:

  • Setup: 8.000 - 25.000 CHF (depending on complexity)

  • Hosting: 50 - 1.000 CHF/month

  • Maintenance: 2-4 Stunden/month

Measurable benefits:

  • 15–25% better campaign performance thanks to more accurate data

  • 10–20% improved conversion rates thanks to optimised attribution

  • Reduced costs thanks to less data loss for iOS users

Break-even:

With monthly advertising expenditure of CHF 5,000 or more, the investment typically pays for itself within 6–12 months.

Understanding compliance and data protection correctly

Important: Server-side tracking does not make consent management redundant. Consent remains mandatory for EU businesses.

The advantage: Data can be classified as ‘technically necessary’ and anonymised in accordance with the GDPR – this does not require explicit consent.

Our experience: Users are more likely to accept tracking if they feel that their data is being handled responsibly. Transparency pays off.

When server-side tracking is worthwhile

Clear recommendation for companies with:

  • Annual advertising expenditure of over 50,000 CHF

  • More than 50,000 website visitors per month

  • Complex customer journeys (B2B, high-priced products)

  • Compliance requirements (banks, healthcare)

Our conclusion: Server-side tracking is no longer a forward-looking technology – it is now essential for data-driven marketing. The question is not whether, but when you will switch.

Next step: Let us evaluate the potential for your company together. A thorough analysis takes 2-3 hours and shows you concrete opportunities for improvement.

Ready for more accurate marketing data? Our digital analytics experts Crispin Sill and Silvan Burnand will support you in evaluating and implementing server-side tracking.

Contact for your Digital Solution with Unic

Book an appointment

Are you keen too discuss your digital tasks with us? We would be happy to exchange ideas with you.

Jörg Nölke
Gerrit Taaks
Gerrit Taaks

Contact for your Digital Solution

Book an appointment

Are you keen to talk about your next project? We will be happy exchange ideas with you.

Melanie Klühe
Melanie Klühe
Stefanie Berger
Stefanie Berger
Philippe Surber
Philippe Surber
Stephan Handschin
Stephan Handschin