What is Google Analytics 4 (GA4)?

Google Analytics 4 (GA4) is Google's free, event-based analytics tool that shows how people find, use and convert on your website and app.

Many business owners still open Google Analytics expecting the old reports. That version, Universal Analytics, stopped processing data in July 2023. Google Analytics 4 replaced it, and it is not a simple redesign. It is a different way of measuring.

In simple words, GA4 is a free tool from Google that records what people do on your website and app, and then helps you understand which visits turn into enquiries, sign-ups or sales.

How GA4 sees your visitors

Universal Analytics was built around sessions and pageviews. GA4 is built around events. A page view is an event. A scroll is an event. A form submission, a video play, a file download and a purchase are all events.

With enhanced measurement switched on, GA4 collects several of these automatically, such as page views, scrolls, outbound clicks, site search and file downloads. You then mark the events that matter to your business as key events. GA4 used to call these "conversions"; since 2024 the term is key events, while Google Ads still uses the word conversions.

GA4 also changed how attention is judged. Instead of focusing only on bounce rate, it reports engaged sessions and engagement rate. An engaged session is one that lasts longer than 10 seconds, includes a key event, or has at least two page or screen views.

A simple example

Imagine a dental clinic in Bengaluru with a website, a "Book Appointment" form and a WhatsApp button. In GA4, the clinic can track the actions that actually matter: form submissions, WhatsApp clicks, taps on the phone number and clicks for directions. Each one becomes a key event.

Now the owner can see which channel brings real patients. Maybe Instagram brings lots of visitors but few bookings, while visitors from the clinic's Google Business Profile link, tagged with UTM parameters, book far more often. That is a business decision, not just a traffic number.

What to set up first

Install the Google tag correctly on every page, directly or through Google Tag Manager.
Mark your real business actions as key events. Not every click deserves that label.
Link GA4 with Google Search Console and Google Ads so search and ad data sit next to behavior data.
Set event data retention to 14 months, the longest option on standard properties, so explorations can look further back.
Filter out internal traffic from your own office and team.
Add a consent banner and Consent Mode if you serve visitors in regions that require it.

Why it matters in the AI era

Some visitors now arrive after reading an AI Overview or asking ChatGPT for a recommendation. Visits from AI assistants often show up as referral traffic, so it helps to create a custom channel group that separates them. This way you can see whether AI search is sending people who actually enquire.

When my team at Thetechhacker audits a client's analytics, the first thing we check is whether key events are firing correctly. A beautiful dashboard built on broken tracking only gives confident wrong answers.

Simple takeaway

GA4 is not just a traffic counter. It is your record of what visitors do and which actions bring business. Set up clean key events, connect your other Google tools, and review it monthly with one question: which channels bring customers, not just clicks?