By 2025, Google Analytics 4 (GA4) has fully replaced Universal Analytics, and most businesses have already made the switch.
Yet, a large number of marketers and media buyers still don’t understand how to properly use GA4 for decision-making.
The result?
— Wrong conclusions
— Poor campaign optimization
— Wasted ad budgets
In this article, I’ll show you how to use GA4 correctly in 2025, what reports actually matter for media buying, how to avoid misleading metrics, and where to focus your attention to optimize your ad spend.
What’s Changed in GA4 — and Why It Matters
GA4 is based on event-driven tracking, not sessions. This gives you more flexibility — but also more confusion if you’re used to the old Universal Analytics model.
Key changes:
- Everything on your site is tracked as an event with parameters
- There’s no clear distinction between “sessions” and “pages”
- Attribution has changed — default is now data-driven
- Standard reports often don’t tell the full story
1. Start With the Right Goals (Conversions)
GA4 automatically tracks basic events, but you need to manually define the conversions that matter to your business:
- Form submissions
- Button clicks (e.g., “Submit application”)
- Chat widget launches
- Page views of specific landing pages
- Purchases
Important: Don’t confuse an event with a conversion — in GA4, you must explicitly mark it as a conversion.
2. Focus on Events, Not Sessions, to Evaluate Ad Performance
In GA4, sessions are not the core unit anymore. If you’re evaluating campaign performance based on traffic or page views, you’re only seeing the surface.
Instead, focus on:
- Events like “lead”, “purchase”, or “submit_form”
- Traffic sources that actually trigger these events
- Which type of traffic brings the highest conversion rate — not just the most clicks
Use Exploration Reports to build custom tables showing conversions by channel, campaign, device, and region.
3. Connect GA4 to Google Ads (and Use the Data)
GA4 offers deeper integration with Google Ads than the old version — but only if you enable it.
Without it, you’re missing out on crucial conversion signals.
Benefits of integration:
- GA4 conversions can be used for Smart Bidding
- You can analyze post-click behavior
- Build remarketing audiences directly in Google Ads
Don’t forget to import your GA4 events as conversions in Google Ads.
4. Understand Attribution — It Works Differently Now
GA4 uses data-driven attribution by default. It gives credit to multiple touchpoints across the customer journey.
This means you won’t see “100% from Facebook” or “just Google Ads” anymore — the value is distributed.
To get clarity:
- Use the Model Comparison Tool
- Review First Click vs Last Click vs Data-Driven models
- Avoid relying on one-touch attribution
5. Build Your Own Dashboards and Reports
Standard GA4 reports can be overwhelming or too limited. That’s why you should:
- Use Explorations to build the reports you need
- Set up dashboards in Looker Studio (formerly Data Studio)
- Create your own “starter” view with key metrics: CPC, CPA, ROAS, CR, LTV
6. Common Mistakes to Avoid in GA4
- Relying only on pageviews
- Judging performance by bounce rate (GA4 measures engagement differently)
- Ignoring custom events — they’re the core of GA4
- Looking only at “users” and “sessions” without business context
7. How GA4 Helps Media Buyers Save Budget
With the right setup (goals, tracking, integrations, reports), you can:
- See which campaigns truly generate leads or sales
- Cut wasted spend early by identifying poor-performing sources
- Understand how users behave post-click and improve UX
- Build remarketing based on actual behavior, not assumptions
Conclusion
GA4 isn’t just a new interface — it’s a new analytics philosophy.
If you learn to read it correctly, you can:
- Reduce your CPA
- Improve your campaign efficiency
- Make confident, data-driven decisions — not guesses
Need help setting up or auditing GA4?
Leave a request — I’ll help you turn your data into actionable results.
