Maximising Website Performance with Google Analytics 4: A Performance Optimisation Guide

Data AnalyticsData Science

What is Website Performance?

Before we get into how Google Analytics 4 (GA4) can optimise your website or digital product’s performance, it’s important to define performance.

When discussing website performance, you may only consider speed. But this is just one of three facets organisations must consider when analysing and optimising websites. 

We categorise these three facets as:

  • Page performance

  • Business performance

  • User experience (UX) performance

While this list is not exhaustive, it’s where organisations find most issues. Let’s define each performance facet and its caretakers.

Page performance

  • What: Page performance is about optimising a website and its page’s speed.

  • Who: Developers and product teams typically work to optimise page performance.

Business performance

  • What: Business performance is about optimising key business and revenue metrics like conversions, churn, etc.

  • Who: Product and marketing teams are typically responsible for these metrics but may include cross-functional partners to solve specific issues.

User experience performance

  • What: User experience performance is about optimising user flows and UI elements to remove friction, making websites and digital products easier to use.

  • Who: Designers typically work with product teams and engineers to solve UX issues.

While these three categories have a different focus, they’re interconnected. For example: 

  • A slow webpage creates a poor user experience, impacting business metrics like conversion and churn rates. 

  • A complex design can create bloat for developers, resulting in a slow website and adversely affecting business performance.

  • An incorrectly-priced product results in poor conversions, no matter how fast your page loads.

Why Measure Performance with GA4?

GA4 introduces groundbreaking features for product development teams and marketers, including custom event parameters and an integrated BigQuery export. These features simplify measuring, analysing, and debugging performance metrics.

  1. Immediate feedback: Unlike other tools with a 28-day aggregation period, GA4 provides insights for developers to determine if changes have led to improvements.

  2. Integration with business metrics: Most companies already use analytics tools to measure crucial business metrics. Having performance data in the same system offers a holistic view of how site performance impacts business outcomes.

  3. In-depth insights: While other tools might indicate a performance issue, they don’t necessarily pinpoint the cause. GA4 allows for capturing additional data, aiding debugging and providing actionable insights.

How can Google Analytics 4 help you improve your website's performance?

GA4 provides a comprehensive view of website traffic, user engagement, and conversions, enabling organisations to identify areas for improvement and make data-driven decisions through the platform’s detailed reporting capabilities.

Here are some of the key ways that GA4 can help you improve your website’s performance:

  • Track key website performance metrics, such as page load times, bounce, and conversion rates: GA4 provides a variety of pre-built reports and dashboards that make it easy to track these key metrics. You can also create custom reports and segments to track specific metrics critical to your business.

  • Identify areas for improvement: With a clear understanding of your website’s performance, you can use GA4 to identify areas where you can improve. For example, you can use the Speed Suggestions report to identify pages with slow load times or the Bounce Rate report to identify pages with high bounce rates.

  • Understand user behaviour: GA4 provides insights into how users interact with your website to improve your design, content, and navigation. For example, you can use Funnel Exploration to see drop-offs or User Explorer to segment users based on their behaviour and interests.

  • Optimise your marketing campaigns: GA4 can help optimise your marketing by providing insights into which campaigns and traffic sources drive the most visitors and conversions. You can also use GA4 to create custom audiences and segments for your marketing campaigns.

These are just some examples of how teams use GA4 data to identify and fix performance issues. GA 4 will tell you where and when issues occur, but you can only understand how and why through further investigation, i.e., screen recording, user interviews, etc.

Understanding Website Performance Data in Google Analytics 4

As we’ve learned, performance doesn’t only relate to speed.

You must evaluate your site’s health based on numerous benchmarks and data points. Marketers assess performance relating to many metrics, including those that deliver business value, like engagement and conversions. User experience and flow optimisation are also critical for a digital product’s performance. 

GA4 provides the tools and features to optimise experiences across multiple devices, platforms, and operating systems. Let’s look at the various ways to approach website performance analysis in GA4.

How to use the Google Analytics 4 reports to track website traffic, user engagement, and conversions

Google Analytics 4 provides a variety of reports and dashboards to track key website performance metrics, such as website traffic, user engagement, and conversions.

Organisations can use GA4 reports to identify issues and bottlenecks to optimise website and campaign performance.

  • Acquisition reports show you where your visitors are coming from, such as search engines, social media, and paid advertising campaigns. 

  • Audience reports show you demographic information about your visitors, such as their age, gender, and interests.

  • Engagement reports show how users interact with your website, page views, time on page/website, and what events they are triggering.

  • Conversions reports show you how many users are completing your desired goals, such as signing up for your newsletter or making a purchase.

Above are a few examples of GA4’s reporting capabilities to optimise website traffic, user engagement, and conversions. The platform provides many reports, including custom ones, to track and optimise depending on your needs and business goals.

How to use the GA4 Funnels report to identify drop-offs and problem areas

The Google Analytics 4 Funnels report shows the path users take through your website to complete a goal, including which pages users are visiting, in what order, and where users are dropping off.

Analysing the root cause of drop-offs might require collaboration between designers, developers, and marketers. 

To use the Funnels report, go to Reports > Conversions > Funnels. Select the goal that you want to analyse and click Create Funnel.

The Funnels report will show you the following information:

  • Path: The sequence of pages users take to complete a goal.

  • Drop-off rate: The percentage of users who dropped off at each page in the funnel.

  • Completions: The number of users who completed the goal.

You can use the Funnels report to identify drop-offs and make necessary adjustments to improve your website and increase conversion rates.

How to compare the performance of different user groups with the GA4 Cohorts report

The Google Analytics 4 Cohorts report allows you to compare the performance of different groups of users over time. For example, you can compare the performance of new users vs. returning users.

You can also compare traffic source performance and where the marketing team must focus to generate more valuable leads.

To use the Cohorts report, go to Reports > Audience > Cohorts. Select the dimension you want and click Create Cohort.

The Cohorts report will show you the following information:

  • Cohort: The group of users that you have created.

  • Metric: The metric to compare, i.e., page views, conversion rate, or revenue.

  • Value: The value of the metric for the cohort.

You can use the Cohorts report to identify which groups of users are performing well and which groups of users need improvement. Once you identify these groups of users, you can target them with specific marketing campaigns and website design changes.

GA4 for page performance and user experience optimisation

With GA4, developers have a powerful tool to measure, analyse, and debug performance metrics effectively. Developers can integrate GA4 with other Google tools to ensure optimal website performance across various metrics.

  1. Emphasise real user data: While tools like Lighthouse and Web Page Test are valuable during development, GA4 complements this data with real-user monitoring (RUM).

  2. Utilise Google’s field data tools: Google offers tools like the Chrome User Experience Report (CrUX) and Page Speed Insights to gauge site performance. While these tools provide a general overview for actionable insights, GA4’s analytics allow deeper analysis.

Integrate with other Google tools: GA4’s compatibility with BigQuery and Data Studio allows for a seamless data flow. This integration facilitates the visualisation and analysis of performance metrics, making it easier to identify and address issues.

How to Debug and Optimise Page Performance Using GA4 and BigQuery

Use this guide to debug your website and discover page optimisation opportunities using GA4 and BigQuery. 

If you find this guide too technical, a Metric Labs Data Analytics expert will work with you to create a bespoke, turnkey solution that meets your business needs. Contact us for a free discovery call and assessment.

Step 1: Choose the right analytics tool
  • If you already use an analytics tool that supports web vitals metrics, stick with it because the results will be comparable, and you’ll waste resources making the switch.

  • If you’re starting fresh, We recommend GA4 due to its BigQuery export feature.

Step 2: Integrate with BigQuery

GA4 allows you to link your property with a BigQuery project so you can automatically populate event data into tables you can query using SQL.

Step 3: Instrument your pages
  • To get your data into BigQuery, you must instrument your pages to capture the data and send it to Google Analytics.

  • Use the Web Vitals JavaScript library to measure web vitals metrics on your site accurately. The library’s GitHub readme provides instructions for integration with various versions of Google Analytics, including GA4.

Step 4: View data in real time
  • Once you’ve added the code to your site, you can view live event data in GA4’s Realtime report.

  • This report showcases core vitals metrics alongside other events like page views. You can drill down into specific events to see all the associated parameters.

Step 5: Set up BigQuery export
  • Navigate to the admin view in GA4.

  • Under the property settings section, click on “BigQuery Linking.”

  • Choose a BigQuery project from the list (create one if none exists).

  • Fill out the required fields and submit.

Step 6: Query Your data in BigQuery
  • Once BigQuery linking is enabled, your GA4 data should appear in your BigQuery project within 24 hours.

  • Each analytics event will be a row in the table, including the web vitals events and their parameters.

  • Run queries to aggregate and analyse your data. For example:

    • Aggregate core web vitals event values over a specific period.

    • View LCP (largest contentful paint) scores for the most visited pages on your site.

  • Rank CLS (cumulative layout shift) scores for each page from worst to best.

Step 7: Identify improvements

Analyse the results to identify pages or metrics that need optimisation. For example, pages with LCP scores above the recommended 2.5 seconds will need performance enhancements.

Optimising Page Performance with Google Analytics 4

You can also use GA 4’s out-of-the-box features and reports to get insights on your page performance, most notably:

  • Page load times

  • Bounce rate

How to use the Google Analytics 4 Speed Suggestions report to identify opportunities to improve page load times

You can use the Speed Suggestions report to identify the pages on your website with the slowest load times and the suggestions that will have the biggest impact on improving the page’s load time.

  1. Go to Reports > Performance > Speed Suggestions.

  2. Select the date range that you want to analyse.

  3. Click on a page to see specific suggestions for improving the page’s load time.

The Speed Suggestions report lists the following information for each page:

  • Page: The URL of the page.

  • Page Load Time: The average time it takes a page to load.

  • Potential Impact: The estimated impact of implementing each suggestion on the page’s load time.

How to use the Google Analytics 4 Bounce Rate report to identify pages with high bounce rates and make improvements

The Bounce Rate report will identify web pages with the highest bounce rates and determine what to fix, i.e., content, design, or navigation.

  1. Go to Reports > Audience > Engagement > Bounce Rate.

  2. Select the date range that you want to analyse.

  3. Click on a page to see the bounce rate for that page.

The Bounce Rate report lists the following information for each page:

  • Page: The URL of the page.

  • Bounce Rate: The percentage of visitors who visited the page and left without navigating other pages on your website.

  • Average Time on Page: The average time visitors spend on the page.

  • Entry Exits: The percentage of visitors who entered your website on the page and left without visiting any other pages.

Optimising page performance is only half the battle. The real challenge? Interpreting the wealth of data GA4 provides to make actionable, impactful decisions for your website.

Understand Your GA4 Reporting to Make Data-Driven Optimisation Decisions

While GA4 is user-friendly and intuitive, without the proper knowledge and expertise, the data is meaningless, and the corrective action isn’t obvious.

Our Metric Labs data analytics experts will work with your team to find and fix issues efficiently. We also suggest improvements to maximise your website’s performance in line with your business goals.

Book a free introductory strategy call with a Metric Labs data analytics expert, and let’s find a solution to meet your needs.


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One response to “Maximising Website Performance with Google Analytics 4: A Performance Optimisation Guide”

  1. “Your blog never fails to make me smile. 😁”

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