Event

In GA4, an event is the basic unit of measurement. Every interaction on your site — a page view, a click, a scroll, a video play, a purchase — is recorded as an event with a name and a set of parameters that describe it. Unlike the old Universal Analytics, which was built around pageviews, GA4 records everything as an event.

Why it matters

The event model is the single biggest conceptual shift between old Google Analytics and GA4. It is more flexible — you can measure almost anything a visitor does — but it also means the data is less neatly packaged out of the box. Understanding that everything is an event helps explain why your reports look the way they do and why two similar-sounding numbers can disagree.

A concrete example

When someone lands on your homepage, GA4 fires a page_view event. If they scroll most of the way down, an automatic scroll event fires. If they click a link to another site, an outbound_click event fires. Each one carries parameters — the page path, the link URL, the scroll percentage. The event count you see in reports is simply the total of all these firings.

The common misreading

People often treat a high event count as a sign of healthy engagement. It usually isn't. A single engaged visitor can generate a dozen events on one page. A page redesign that adds more automatic tracking can double your event count overnight without a single extra visitor. Read event count alongside sessions and users, and pay attention to which events are key events — those are the ones tied to business outcomes.