Google Analytics (GA4): Key Metrics, Organic Traffic & Conversions
Search Console tells you "how users arrive"; Google Analytics tells you "what they do after arriving." GA4 is the other half of measuring SEO's real value—traffic alone isn't enough; you also need to see whether that organic traffic brings engagement, interaction, and conversions. This article explains GA4's event model, key metrics, how to view organic traffic separately, how to link with GSC, and how to set up conversions.
GA4 Basics#
GA4's biggest feature is that it's event-based: pageviews, scrolls, clicks, form submissions, and all interactions are recorded as "events," rather than sessions and pageviews being the only core. Understand a few core objects:
| Concept | Meaning |
|---|---|
| Event | A single user interaction, GA4's basic unit |
| User | A unique visitor |
| Session | A continuous visit |
| Key event | A business-valuable event (i.e., conversion) |
Key Metrics#
- Users / Sessions: Visit scale;
- Engagement rate / average engagement time: Whether content is engaging;
- Traffic source: Where users come from (organic search, direct, referral, social, paid);
- Key events (conversions): Whether valuable actions were completed;
- By page / landing page: Which content brings traffic and conversions.
Isolate Organic Traffic#
To measure SEO you must isolate organic search traffic, otherwise it's mixed with direct, paid, and social and hard to read. In reports, filter the default channel grouping to Organic Search, or use the session source/medium dimension to view specific search engine sources.
Link with Search Console#
GA4 itself can't see what search terms users used. After linking Search Console to GA4, you can see queries, impressions, and clicks inside GA4, connected to on-site behavior and conversions—forming the full "search → arrival → conversion" path. Set it up under product associations in the GA4 admin backend.
Set Up Conversions (Key Events)#
- Define what counts as a valuable action: registration, form submission, purchase, download, contact, etc.;
- Confirm these actions have corresponding events (Enhanced Measurement auto-collected, or custom events);
- Mark it as a key event in event settings;
- Analyze key events by channel in reports to measure the real value brought by organic traffic.
Privacy & Compliance#
Deploying analytics must comply with applicable privacy regulations (like consent management, cookie notices). This is beyond this article's scope, but you should confirm compliant configuration before launch. GA4 is designed to be more privacy-adaptive, but compliance responsibility still lies with the site owner.
Frequently Asked Questions#
How does GA4 differ from the old Universal Analytics?
GA4 uses an event-based data model—all interactions are recorded as events—while the old Universal Analytics centered on sessions and pageviews. GA4 measures web and app uniformly, focuses more on users and conversions, and is more privacy-adaptive. Universal Analytics has stopped processing data, so you should use GA4 now. Those used to the old metrics need to adapt to the new concepts and report structure.
How do I view only organic search traffic in GA4?
In reports, filter by the traffic acquisition dimension and select Organic Search from the default channel grouping to see traffic from organic search engine results. You can also use the session source/medium dimension to view specific sources. Isolating organic traffic is the only way to accurately measure SEO effectiveness, rather than mixing it with direct, paid, and social traffic.
Should I link GA4 with Search Console?
Recommended. After linking your Search Console property in the GA4 admin backend, you can see search queries, impressions, clicks, and other GSC data inside GA4, analyzed together with on-site behavior and conversions. This connects the full path from search to on-site behavior, compensating for GA4's inability to see search terms on its own.
How do I set up conversions in GA4?
GA4 measures behavior with events; you mark business-valuable events as key events (earlier called conversions), such as form submission, registration, purchase, download, etc. You can use Enhanced Measurement auto-collected events or custom events, then mark them as key events in event settings. After setup, you can analyze the completion of these key events by channel in reports to measure the real value of organic traffic.