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True or False: GA4 is more accurate than Universal Analytics

For many years now, Universal Analytics (UA) has been the cornerstone of the digital marketing world. The current version of Google Analytics has evolved from its humble roots way back in 2005 and marketers have been using the various iterations of the platform to understand their digital marketing performance ever since. 

However, Google’s latest release, Google Analytics 4 (GA4), has been the cause of much commotion throughout the marketing community due to some fairly big changes in the way the platform works and how it presents data. 

One key concern is around the accuracy of the data provided in GA4, which all comes down to cookies. In fact, third-party cookies, along with wider privacy concerns, have been one of the integral reasons for Google’s development of GA4. 

With users globally pushing for increasingly strict personal privacy measures, the traditional third-party cookie-based methods used until now to track users online are becoming less acceptable in a privacy-first online world. 

In this evolving landscape, Google has built GA4 to provide a more flexible, blended approach to measurement and analytics, cleverly designing the platform to survive the transition from using cookies and personal identifiers to a ‘cookieless’ future

As part of this new approach, Google has identified the potential risk of data gaps due to the loss of cookies. So, unlike its predecessors, GA4 makes use of Google’s latest machine learning algorithms to enable statistical modelling – essentially extrapolating trends found in your dataset to fill in gaps left behind by the ever-declining use of cookies.

The question remains, will the cookieless GA4 be as accurate as UA? To explore this we’ll take a look at some of the ways GA4 differs from the current UA platform. 

GA4 Tracking enhancements

GA4 includes improved tracking capabilities that, instead of relying heavily on session data, allow it to collect more ‘event-based’ data about user interactions with your site or app. These capabilities are designed to provide a more comprehensive view of user behaviour and provide a better understanding of how users interact with your site.

For example, rather than being limited to seeing how many sessions or user-defined conversions have occurred on a page, GA4 comes pre-loaded with ‘enhanced measurement’ events which show user interactions specific elements on a page such as interaction events with buttons, outbound links, videos, forms, and other types of content.

Flexible event tracking in GA4 

For events that don’t come under GA4s ‘automatically collected’ or ‘enhanced measurement’ categories, it’s far easier to set up custom events and parameters than in UA. This allows you to track more events, more accurately without having to create custom code or technical Google Tag Manager implementation. To learn more about GA4 events check out our latest article on understanding GA4 events and conversions. 

A broader view of tracking

If you’re trying to understand user behaviour across multiple devices, such as desktop, mobile or tablet; or indeed across multiple platforms such as your website and mobile apps, GA4 offers unmatched accuracy. This is due to how UA uses cookies to establish user identity. In this case, a new ‘Client ID’ is assigned to each GA cookie for each device used to visit the website, leading to duplication and the need for more complex cross-device tracking implementations. 

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A new mechanism for sessions

Sessions and page views have always been somewhat questionable, with many ways a user may trigger additional sessions or falsely represent true user behaviour. In UA, sessions end after a certain amount of inactivity, changing session campaign source, or even passing midnight. In GA4, sessions are initiated by the ‘session_start’ event after which a user can continue a session for an indefinite period until leaving or becoming inactive. This negates a lot of the previous issues from UA, leading to more accurate measurement.

There are, however, some differences to how this is calculated. As we cover in our recent article, GA4 uses an estimation to provide its session count. The event-based platform logs each session start as a separate event, meaning it has to use a statistical estimate to provide a unique session count. As with all machine learning, the quality of output is heavily dependent on the input – which may cause accuracy issues for smaller sites with lower traffic volumes.

Easy integration with Google tools

Whilst less related to accuracy, GA4 is better integrated with platforms such as Google Ads and Google BigQuery, which can help with analysing data more holistically rather than broken out into separate places. Taking Google Ads specifically, GA4 offers more insight into user behaviour and conversion events through enhanced integration. This also enables GA4 users to pass useful information back to Google Ads, such as audience segments to target through ads. 

So, it’s difficult to determine exactly how the accuracy of UA and GA4 compare due to the range of differences in the way the two platforms collect and interpret data. Overall, it seems GA4 is at least as accurate as UA, but in some areas such as cross-device tracking, it may offer significant advantages. It is also apparent that GA4 offers a more holistic and comprehensive set of tools and features. 

More importantly, the accuracy of your analytics is determined by having the correct configuration, setup and maintenance. Here at Door4, we focus on helping businesses bridge the gap between UA and GA4 in the most accurate and stress-free way possible…

Are you GA4 Ready?

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Solid insight into migration, tracking and reporting – and a chance to get a view on your next important steps.
We don’t need any UA/GA4 credentials – we will offer to screen-share with you during the session if you want direct ‘in-platform’ assistance. Book your session now!


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