UA vs GA4: Bounce Rate & Engagement Rate Explained

The transition from Universal Analytics (UA) to Google Analytics 4 (GA4) marks a significant shift in how we understand and measure user interactions on websites and apps. Universal Analytics, which focused heavily on page views and sessions, often relied on bounce rate as a key metric for user engagement. However, as websites and applications became more complex, the limitations of UA’s bounce rate became apparent. GA4 addresses these limitations by introducing new metrics such as the GA4 bounce rate, engagement rate, and engaged sessions that better capture user engagement. This blog post provides an introduction to these changes.

Understanding Universal Analytics’ Bounce Rate

What was a bounce in UA?

A bounce in UA occurred when a user viewed only one page on a website and did not interact with the page.

How was bounce rate calculated in UA?

In Universal Analytics, bounce rate was defined as the percentage of sessions in which the user viewed only one page and did not interact with the page (i.e. bounced). This is how UA calculated it:

The image shows how Universal Analytics calculated bounce rate (bounces were divided by sessions and then the result was multiplied by 100).

What were the limitations of bounce rate in UA?

Although many used bounce rate as a metric for analyzing user engagement, it had significant limitations including:

  • Time On Page – UA’s bounces didn’t consider how long a user spent on the page. For example, a user spent over 3 minutes reviewing the homepage of a website and then exited without interacting further. UA would have considered that session a bounce, even though the user spent significant time engaged with the site.
  • Engagement Context – UA’s bounces didn’t account for meaningful engagement that occurs on a single page, such as scrolling through a lengthy article.

Understanding GA4’s Bounce Rate and Engagement Rate

What are engaged sessions in GA4?

GA4 introduced the metric of engaged sessions to address the limitations of UA’s bounce rate. In GA4, a session qualifies as engaged if it meets any of the following criteria:

  • Lasts longer than 10 seconds, or
  • Includes one or more key events, or
  • Involves two or more pageviews or screenviews

What is a bounce in GA4?

GA4 redefines bounces to give a more holistic view of user engagement by using the new metric of engaged sessions. In GA4, a bounce refers to a non-engaged session, meaning a session that doesn’t meet any of the criteria outlined above.

How is bounce rate calculated in GA4?

Since bounces are non-engaged sessions, GA4’s bounce rate represents the percentage of sessions that are not engaged. GA4 uses the same bounce rate calculation as UA (shown below). The key difference is that bounce is defined differently.

The image shows how GA4 calculates bounce rate (bounces are divided by sessions and then the result is multiplied by 100).

How is engagement rate calculated in GA4?

GA4 introduces engagement rate, which is the percentage of engaged sessions. In GA4, engagement rate is the inverse of bounce rate. This is how GA4 calculates it:

The image shows how GA4 calculates engagement rate (engaged sessions are divided by sessions and then the result is multiplied by 100).

Frequently Asked Questions about Bounce Rate & Engagement Rate

How should I use GA4’s Engagement Rate?

We recommend visualizing landing pages by their engagement rates to identify top performing pages and investigate those that are underperforming. A low engagement rate on a landing page might suggest underlying issues, such as broken hyperlinks, confusing language, or intrusive pop-ups. Make sure to look at sessions and engagement rate simultaneously to avoid skewed results. For example, a page with a 100% engagement rate but only two sessions may not provide reliable insights.

Is UA’s bounce rate the same as GA4’s bounce rate?

No, UA and GA4 define bounces differently. A bounce in UA occurred when a user viewed only one page on a website and did not interact with the page. A bounce in GA4 is a non-engaged session (i.e. a session that didn’t meet any of the criteria for an engaged session laid out above).

Is GA4’s bounce rate the inverse of GA4’s engagement rate?

Yes, GA4’s bounce rate is the inverse of GA4’s engagement rate. However, UA’s bounce rate is not the inverse of GA4’s engagement rate, because UA and GA4 define a bounce differently.

Is staying on my website for 10 seconds truly an engaged session?

According to Google, yes. However, depending on your website, you might not consider 10 seconds to be an engaged session. In this case, you can adjust the timer for engaged sessions to 20, 30, 40, 50, or 60 seconds within your GA4’s settings. This allows you to capture more accurate user engagement levels for your unique site.

Conclusion

The shift from Universal Analytics to Google Analytics 4 marks a pivotal change in how we analyze and interpret user interactions. By understanding the limitations of UA and embracing the advanced metrics of GA4, you can gain deeper insights into user behavior.

Need additional help with Google Analytics 4? Check out our Google Analytics consulting services today!

Moriah Glidden

Data Analytics Intern