Website performance is part of the customer experience

Measure what visitors experience

Google’s Core Web Vitals focus on three user-experience dimensions: loading, interactivity and visual stability. Largest Contentful Paint (LCP) measures when the main content is likely visible. Interaction to Next Paint (INP) measures responsiveness to user interactions. Cumulative Layout Shift (CLS) measures unexpected layout movement. These metrics make performance work more concrete than “the page feels slow.”

Start with the largest bottlenecks

Large hero images, unnecessary scripts, slow server responses and blocking styles often have more impact than tiny code optimisations. Compress and correctly size images, use modern formats where appropriate, lazy-load below-the-fold media, remove unused third-party tags and cache static assets. Keep fonts and JavaScript loading intentional.

Test more than the homepage

Check service pages, blog articles, contact forms and pages with heavier media. Test representative mobile devices and network conditions. A site can perform well on one desktop and poorly on a mid-range phone. Compare lab diagnostics with field data when available; they answer different questions.

Protect interaction quality

A page is not fast if the menu, form or chatbot becomes unresponsive after it loads. Break up expensive JavaScript work, avoid unnecessary animations and ensure controls provide immediate feedback. Test keyboard use and reduced-motion preferences alongside visual performance.

Make it a release habit

Record a baseline, set practical performance budgets and re-check the same key pages after major releases. Track the metrics alongside conversion and form completion. Performance improvement is continuous: new content, images, analytics tags and embedded tools can change the experience.

Putting the ideas into practice

A strong performance programme is user-led: find the pages and actions that matter, measure them consistently, fix the largest bottlenecks and validate again. Use performance data to guide decisions, not as a badge to display without context.