How to use web analytics to optimise your website’s frontend? Part one: tools and metrics

Seemingly minor frustrations can determine whether a website visit ends in a conversion or a closed browser tab. Loading speed, readable content and intuitive navigation can make all the difference. This is why frontend development is about more than aesthetics and keeping up with UX trends: it also plays a direct role in supporting business goals. 

But how do you know what works and what needs attention? Web analytics helps you see your website through the behaviour of the people using it. It reveals how visitors interact with the site and where they encounter difficulties, giving marketers, website owners and technical teams the insight they need to make informed decisions and assess the impact of their changes. 

In the first part of this article, we explore the tools and metrics that help build a clearer picture of frontend performance. In part two, we move from observation to action, showing how to use those insights to optimise your website and test potential improvements. 

Why does web analytics matter for the frontend? 

Most websites serve specific business purposes: supporting sales, generating enquiries and providing information. The frontend – the visual and interactive layer of a website – should make these tasks easier for users. A well-designed menu, a clearly presented offering and a form that works smoothly therefore have a value that goes far beyond appearance. 

During the design stage, however, you can only make assumptions about how people will use the site. Data allows you to put those assumptions to the test. It shows which elements visitors use, where they drop off and which interactions lead to a successful outcome, such as a purchase or form submission. For the teams responsible for the website, this creates a basis for design decisions grounded in observed behaviour. 

The frontend and user experience 

Loading performance, access to features, content readability and intuitive navigation all shape the user experience, or UX. Even the most visually appealing website can put people off if it takes too long to load or behaves unpredictably. Useful indicators of how visitors interact with a site include: 

  • engagement time,
  • bounce rate,
  • click-through rates for call-to-action buttons and links,
  • progression through the conversion journey. 

These metrics do not capture the entire user experience, but they help identify areas that deserve closer attention. 

Turning data into action 

The value of analytics becomes clear when insights inform decisions about the website. Frequent basket abandonment, for example, may point to difficulties in the purchasing process, while a low CTA click-through rate may suggest a problem with the button’s visibility or placement. 

These signals offer a useful starting point for diagnosing what is going wrong. Data alone does not establish the cause, but it helps determine what to investigate before making changes. 

Connecting analytics with business goals 

For marketers and website owners, analytics also supports decisions about the website’s future development. It helps teams understand users’ needs, identify opportunities to improve conversion, build a case for frontend changes or investment, and monitor the efficiency of product initiatives and campaigns. In this way, work on the interface becomes clearly connected to business goals. 

Tools for frontend analysis 

Understanding what happens on a website means looking at it from several perspectives. Optimisation brings together quantitative data, observations of user behaviour and technical measurements. The right tools help establish what is happening and investigate the reasons behind any problems. 

Google Analytics 4 – quantitative analysis 

How many people visit your website? Where do they come from? What do they do once they arrive, and do they reach their goal? Google Analytics 4 helps answer these questions by enabling analysis of: 

  • user and session numbers,
  • traffic sources,
  • engagement time,
  • events and goal completion,
  • paths leading to conversion. 

For frontend teams, GA4 helps assess the effectiveness of individual pages and identify the stages at which users abandon their journey. 

Google Tag Manager makes it easier to configure tracking for clicks on buttons, menus and other interface elements. Depending on how the website works, some tracking can be implemented without changing the code, while other measurements require developer support. 

Hotjar and Microsoft Clarity – understanding user behaviour 

Numbers reveal the scale of an issue, but they do not always explain it. Tools such as Hotjar and Microsoft Clarity add another perspective through features including: 

  • heatmaps showing where users click and how far they scroll; 
  • session recordings that let teams follow interactions with the interface; 
  • signals of potential difficulties, such as repeated clicks or clicks on elements that do not respond. 

These observations help uncover problems with page layout, content readability and interactive elements that may remain hidden in numerical reports. 

PageSpeed Insights and Lighthouse – website performance and quality 

Sometimes, the obstacle lies in how well the website itself performs. PageSpeed Insights helps assess performance on mobile and desktop devices. It combines a laboratory test with real-user experience data, where available, and allows teams to check Core Web Vitals. Lighthouse, meanwhile, provides automated audits covering performance, accessibility, best practices and SEO. 

Important!
Both tools offer useful guidance for planning improvements. An automated accessibility audit, however, is a starting point for further investigation rather than a complete assessment of the website. 

WebPageTest – a closer look at loading performance 

When a website is slow, it helps to understand what the browser is waiting for. WebPageTest allows teams to examine the loading process using different device, connection and test-location settings. It can be used to: 

  • compare website performance under different conditions,
  • analyse the sequence and timing of resource downloads using waterfall charts,
  • investigate the impact of external resources, such as fonts, adverts and plugins,
  • identify elements that delay content appearing on screen. 

This allows teams to investigate performance issues in greater depth and assess how the website behaves under conditions similar to those experienced by its visitors. 

Chrome DevTools – tools for developers 

Chrome DevTools supports more technical frontend analysis, including: 

  • analysing network requests and resource loading in the Network panel,
  • inspecting page structure and styles in the Elements panel,
  • profiling website performance in the Performance panel,
  • overriding resources locally using the Overrides feature,
  • simulating selected devices and network constraints. 

Although primarily intended for developers, the findings can help explain issues visible in marketing reports, such as interactive components that respond slowly. 

Frontend metrics – what should you measure, and how? 

Tools provide a wealth of data. The skill lies in selecting the information that answers specific questions about your website. Combining technical measurements with conversion analysis and observations of user behaviour is particularly useful: each perspective reveals a different part of the user experience. 

Core Web Vitals 

Core Web Vitals are a set of metrics describing loading performance, responsiveness and visual stability. They help assess whether using a website feels smooth or requires patience. 

  • LCP – Largest Contentful Paint measures how long it takes for the largest content element within the viewport to appear. A good result is 2.5 seconds or less. 
  • FID – First Input Delay assesses how quickly the website responds to a user’s first interaction, such as clicking a button. A shorter FID indicates a more responsive experience. 
  • CLS – Cumulative Layout Shift measures unexpected shifts in page elements. A high CLS can frustrate users and make the website harder to use. 

Core Web Vitals provide a technical assessment of user experience quality and are taken into account by Google’s ranking systems. Improving them does not, however, guarantee higher rankings or more conversions. 

Conversion rate and engagement 

Conversion rate shows the proportion of users or sessions that result in a desired action, such as a purchase or newsletter subscription. When comparing results, it is essential to use the same definition consistently. Otherwise, it is easy to compare figures that describe entirely different things. Supporting metrics include: 

  • average engagement time,
  • page views per session,
  • returning users,
  • interactions with buttons, forms and tabs. 

Changes in these metrics may indicate difficulties with navigation, access to content or the relevance of the offering. They must, however, be interpreted in the context of the website’s purpose. A longer visit does not always mean a better experience: it may also reflect difficulty finding information. 

Important!
In GA4, bounce rate is the percentage of sessions that were not considered engaged sessions. It is therefore not simply a measure of visits that ended after viewing a single page. 

CTA efficiency 

Buttons, banners and links that encourage action should be easy to read and positioned logically. Useful measures include: 

  • click-through rate – clicks relative to the number of times an element was displayed; 
  • visibility – whether the user had an opportunity to see the CTA; 
  • time to click – the time elapsed before an interaction. 

These insights make it easier to assess whether users reach and interact with a CTA. On their own, however, they do not explain why a button is being overlooked. 

Heatmaps and session recordings 

Behind every figure in a report are individual visits. Heatmaps and session recordings let teams examine those visits more closely: where users click, how far they scroll, what they do before leaving and which interface elements may cause difficulties. 

They provide a useful complement to quantitative metrics, helping identify usability problems and develop hypotheses that can then be tested. 

User journeys and drop-off points 

Path analysis examines how users move through a website and where they leave the conversion process. In GA4, tools such as path explorations and funnel explorations support this work. 

Identifying drop-off points directs attention towards the parts of the website that need closer investigation, such as a form, basket or the transition from an offering page to an enquiry. Rather than asking broadly why the website is not converting, teams can focus on the stage at which users most often stop. 

Conclusion: Using data as a starting point for optimisation 

To the people who created it, a website may seem clear, convenient and entirely intuitive. Analytics helps establish how it actually performs in everyday use. Combining observations of user behaviour with technical measurements makes it easier to identify difficulties, distinguish observed problems from assumptions and decide which areas need attention first. 

The next step is to implement changes and check whether they genuinely make the website easier to use. That is the focus of part two, where we explore optimisation techniques, A/B testing and collaboration in frontend development.

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