This year is an important year for Google Analytics, especially with the rollout of GA4. But what does it mean for businesses, and what are the differences?

How did the Google Analytics journey start?

Universal Analytics (GA3) was introduced in November 2005.

The incredibly fast evolution of the Internet between 2002-2022 forced even the largest data holders to re-evaluate their policies.

In March 2005, the number of internet users was 888 million which was 13.9% of world population. And in December 2022 the number of internet users was 5.54 billion which was 69% of world population.

This has meant that the amount of data that is flowing through the internet has increased exponentially, and it could have been one of the factors that made Google rethink how they were going to collect and manage all that data. Considering the amount of users online, GA4 looks at event as a foundation, rather than sessions, and the change could have been dictated by the amount of data flow.


Google Analytics has undertaken many updates and iterations since its inception, and the most recent version is GA4, which will replace Universal Analytics once it stops collecting data in July 2023.


What are the key differences between GA3 and GA4?

The main difference is session vs. events.

GA3 (Universal Analytics) uses measurement based on sessions and pageviews whereas GA4 uses a measurement model based on events and parameters.

What’s important is that every activity taken by a user will be counted as an ‘event’ in GA4. It means that you’ll end up with much more detail on how users are engaging with your website.

In Universal Analytics, a session is a combination of page views, events, transactions or more taken by one user within a given timeframe. You can think of a session as a container for all the actions a user takes while on your site.

In contrast, Google Analytics 4 sessions aren’t limited by time. Since it doesn’t create new sessions for source changes mid-session, your session count will likely be lower.

Given this change, your average session time will drastically change as well. And remember, average pages per session is no longer measured in GA4.

What has disappeared?

Bounce rate has been scrapped, and engagement rate is taking its place.

Instead of only looking at visitors who don’t move to another page on the website, engagement rate also considers the time spent on the landing page. This difference makes engagement rate and bounce rate incomparable.

Google Analytics 4 offers a range of engagement metrics including engaged sessions, engagement rate and engaged sessions per user.

What makes GA4 so special?

A really great benefit is the cross-platform tracking.

One of the most powerful features of GA4 is its ability to track users across devices and platforms. This means that you can get a complete picture of how your users interact with your brand, whether they’re on your website, your mobile app, or both.

The other big advantage of this is that it makes it much easier to track conversions since you can see the entire journey a user takes from start to finish, regardless of what device or platform they’re using.

Another benefit is the better insights with machine learning.

GA4 uses ‘probabilistic matching’ to stitch together data from different sources and gives you a more complete picture of your users.

For example, let’s say you’re running a campaign on both Google Ads and Facebook Ads. GA4 can use probabilistic matching to match up the data from those two campaigns and give you a single view of how they’re performing.

Another exciting new feature of GA4 is its ability to predict purchase probability and churn for each individual user. Purchase probability measures how likely a user is to purchase on your website or app. Churn measures how likely a user is to stop using your product.

This means that you can target your marketing efforts more effectively and focus on the most likely users to convert or churn.


Pawel Lorenc, Director of Data and Insight


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