What Is Google Analytics 4?
Google Analytics 4 (GA4) is Google's current generation analytics platform, which replaced Universal Analytics (UA) in 2023. It represents a fundamental shift in how website activity is tracked — moving from a session-based model to an event-based model. This change gives marketers more flexibility in measuring user behaviour across websites and apps, but it also comes with a learning curve for those familiar with the older system.
Event-Based vs. Session-Based Tracking: What's the Difference?
In Universal Analytics, the core unit of measurement was the session — a period of activity on your website. In GA4, every interaction is tracked as an event. Whether someone views a page, clicks a button, watches a video, or submits a form — it's all captured as an individual event.
This approach is more granular and flexible, but it means that many of the familiar metrics (like "bounce rate") have been redefined or replaced in GA4.
Key GA4 Concepts You Need to Know
Events and Parameters
GA4 automatically collects several events out of the box, including page views, session starts, first visits, and scroll depth. You can also set up custom events to track specific actions important to your business, like form submissions or file downloads.
Engagement Rate
GA4 replaced the old bounce rate metric with engagement rate — the percentage of sessions where a user was actively engaged (spent more than 10 seconds on the page, triggered a conversion, or viewed multiple pages). A higher engagement rate generally indicates more relevant, quality traffic.
Users vs. New Users
GA4 distinguishes between total users, new users, and returning users. Understanding this split helps you assess whether your acquisition efforts are bringing in new audiences or primarily re-engaging existing ones.
Conversions
In GA4, conversions are simply events you've marked as important. You can mark any event — like a form submission, purchase, or newsletter sign-up — as a conversion goal, giving you a clear picture of what actions drive business value.
The Most Important GA4 Reports for Marketers
| Report | Where to Find It | What It Tells You |
|---|---|---|
| Traffic Acquisition | Reports > Acquisition | Where your visitors are coming from (organic, social, email, direct, paid) |
| Engagement Overview | Reports > Engagement | Which pages and content users interact with most |
| Conversions | Reports > Engagement > Conversions | How many key actions (goals) are being completed |
| User Demographics | Reports > Demographics | Age, gender, location, and interests of your visitors |
| Tech / Device | Reports > Tech | What devices and browsers visitors use |
| Retention | Reports > Retention | How often users return to your site |
Setting Up GA4 Correctly from the Start
- Create a GA4 property in Google Analytics and add the tracking code (G-tag) to your website.
- Enable enhanced measurement to automatically track scrolls, outbound clicks, site searches, and video engagement.
- Mark key events as conversions based on your business goals.
- Connect to Google Search Console for organic search performance data inside GA4.
- Set up UTM parameters for all campaign links so you can accurately attribute traffic sources.
Using GA4 to Make Better Marketing Decisions
Raw data only has value when it informs action. Use GA4 insights to:
- Identify your best-performing traffic channels and invest more there
- Find high-traffic pages with low engagement and improve their content
- Discover which content leads users toward conversion
- Spot drop-off points in your conversion funnel
- Understand which devices your audience uses to optimise their experience
Final Thoughts
GA4 has a steeper learning curve than its predecessor, but it's also far more powerful. Take time to explore the interface, customise your reports, and — most importantly — tie your analytics data back to real business questions. The goal isn't to collect data; it's to understand your audience well enough to serve them better.