What you need to know about Google Analytics 4 (GA4)

Jan 10, 2022


by | Jan 10, 2022 | Marketing ops, Technology


Google Analytics is used by 56.7% of all websites and is the most widely used analytics platform on the web. 

Since its launch in 2005, Google has launched 4 iterations, the newest version GA4 launched in October 2020. GA4 is a big change and while it offers new features for marketers it collects data in a very different way. 

Here’s what you need to know about GA4.

So why the big change?

A lot of marketers have been using Google Universal Analytics (UA) for years, so why fix something that isn’t broken? 

There are three reasons for the change:

1. We can compare apps and websites as the data collection is the same

2. We can use machine learning (ML) to predict what’s likely to happen on your site

3. We can use the ML to fill some of the gaps that GDPR has made in recorded data

Combining app and website analytics

Websites and apps don’t track data in the same way. Marketers rely on UA to collect website data and Firebase to track app data. 

GA4 combines the best of both, it allows all the data to be under one umbrella, making it easier for marketers to collect and compare all of the information. 

You’ll be able to find out information like: 

  • How people engage with your website compared to your app e.g. how many conversations have occurred from your website vs how many have occurred via the app
  • The effectiveness of your marketing campaigns across the platforms, i.e. how many users started on your app and then visited your website

Machine Learning – a sophisticated data analysis tool

Google is now using Machine learning across multiple products:

  • RankBrain is being used to run tests and optimise search results to get the best click-through and user experience
  • Search Ads 360 uses ‘Smart Bidding’ which “automates the bidding process to improve campaign performance and help you get more from your marketing budget”   

With GA4 there are some amazing predictive analytics built-in and more to come.

You can learn a lot about your customers using predictive metrics such as:

  • Purchase probability: The probability that a user who was active in the last 28 days will log a specific conversion event within the next 7 days
  • Churn probability: The probability that a user who was active on your app or site within the last 7 days will not be active within the next 7 days
  • Revenue prediction: The revenue expected from all purchase conversions within the next 28 days from a user who was active in the last 28 days

Currently, only purchase/ecommerce_purchase and in_app_purchase events are supported for the purchase probability and revenue prediction metrics.

GDPR and privacy

GDPR and the abolishment of third-party cookies has affected how website and app data is utilised, and can cause a loss in recorded traffic.

If you aren’t sure, check ‘Search Console’ to see if impressions have been affected over time. If organic traffic has gone down in GA but Search Console doesn’t show the same trend, then chances are, your traffic hasn’t been affected but the recording of it has.

Google has said that it will use Machine Learning to bridge the gap, so you can estimate how much traffic you should be getting.

If Google is changing the data set in GA4, then it could mean that the traffic between GA4 and the current Universal Analytics isn’t comparable.

A different way of recording data

To allow Apps and Websites can have comparable data, GA4 only uses Events. So, where UA uses page views and sessions, GA4 only uses events (and records things like page views as an event), this brings with it a massive amount of flexibility but….

Events are different

UA used 4 parameters:

  • Event Category (category is required)
  • Event Action (action is required)
  • Event Label (the label is optional)
  • Event Value (value is optional)

GA4 has a more flexible set-up:

  • Event Name (event name is required)
  • Additional Parameter 1 (you can choose whatever parameter you want and name the parameter however you want)
  • Additional Parameter 2 (you can choose another parameter of whatever you want and name it as you choose)
  • Additional Parameter 3 (etc., etc.)
  • Additional Parameter 4 (you get the idea)

In GA4 page views and sessions are included in  ‘automatically-collected events’. So, by default, you’ll have ‘core metrics’, like page views and users running. 

For example, one very powerful change is that history state changes (which is where page content is dynamically served without reloading the page), will automatically trigger a new event page view. In UA these had to be triggered manually and required significant set-up.

What you need to do:

  • Run UA and GA4 alongside one another and compare
  • Look at your custom events and migrate them
  • Look at reporting and see what the differences are
  • Explain to and warm-up report recipients to let them know that the data is going to change and why
  • And lastly, contact us if you need any help!


Are you ready to migrate?
We have a dedicated Digital Team who have helped clients migrate to GA4 smoothly. If you’d like to have a conversation about how we can help you, then contact us today.

Further reading

The impact of the strategic skills gap in marketing technology

When conversion tracking goes wrong, everything gets shaky

Leading change: Unpacking the Forrester B2B Summit, North America