Website Speed Test

What is PageSpeed?

Google PageSpeed Insights is a performance analysis tool that evaluates how well a web page performs on both mobile and desktop devices. It combines two types of data: lab data (simulated page loads in a controlled environment using Lighthouse) and field data (real-world performance metrics collected from actual Chrome users via the Chrome User Experience Report).

Lab data is useful for debugging specific issues because it is reproducible and detailed. Field data reflects the actual experience of your visitors, which can vary based on their devices, network conditions, and geographic location. When both are available, field data is generally more representative of real user experience.

Core Web Vitals

Core Web Vitals are Google's standardised metrics for measuring real-world user experience. They focus on three critical aspects of page performance:

• LCP (Largest Contentful Paint) — Measures loading performance. This is the time it takes for the largest visible content element (usually a hero image, heading, or text block) to finish rendering. Good: under 2.5 seconds. Needs improvement: 2.5-4.0s. Poor: over 4.0s.
• INP (Interaction to Next Paint) — Measures interactivity. This replaced FID (First Input Delay) in 2024. INP tracks the latency of all user interactions (clicks, taps, keyboard inputs) throughout the page lifecycle, reporting the worst interaction. Good: under 200 milliseconds. Needs improvement: 200-500ms. Poor: over 500ms.
• CLS (Cumulative Layout Shift) — Measures visual stability. Tracks how much visible content unexpectedly shifts during page load. A high CLS means elements are jumping around, which is frustrating for users (especially when they try to click something that moves). Good: under 0.1. Needs improvement: 0.1-0.25. Poor: over 0.25.

Score Categories

PageSpeed Insights evaluates your site across four categories, each scored from 0 to 100:

• Performance — Overall page speed based on loading time, interactivity, and visual stability. Calculated from a weighted combination of metrics including LCP, INP, CLS, Total Blocking Time, and Speed Index.
• Accessibility — How usable your site is for people with disabilities. Checks include colour contrast ratios, proper heading hierarchy, image alt text, ARIA labels, keyboard navigation, and form labels.
• Best Practices — Modern web development standards including HTTPS usage, absence of console errors, correct image aspect ratios, and avoidance of deprecated APIs.
• SEO — Search engine optimisation basics such as valid meta descriptions, crawlable links, proper status codes, mobile viewport configuration, and readable font sizes.

Scores are colour-coded: green (90-100) is good, orange (50-89) needs improvement, and red (0-49) is poor.

Common Issues and Fixes

The most impactful optimisations you can make:

• Optimise images — Use modern formats like WebP or AVIF instead of PNG/JPEG. Serve responsive images with srcset. Lazy-load images below the fold. This alone often improves LCP by 30-50%.
• Eliminate render-blocking resources — Defer non-critical CSS and JavaScript. Inline critical CSS. Use async or defer attributes on script tags.
• Fix layout shifts — Always set explicit width and height on images and videos. Reserve space for dynamically loaded content like ads or embeds. Use CSS aspect-ratio for responsive containers.
• Reduce JavaScript — Remove unused code with tree shaking. Split bundles so only necessary code loads on each page. Avoid heavy client-side frameworks when simpler alternatives suffice.
• Improve server response time — Use a CDN, enable server-side caching, upgrade to faster hosting (LiteSpeed or Nginx), and optimise database queries. Target a Time to First Byte (TTFB) under 200ms.
• Enable compression — Use Gzip or Brotli compression for text-based assets (HTML, CSS, JavaScript). This typically reduces transfer sizes by 60-80%.

How Speed Affects SEO

Page speed is a confirmed Google ranking factor. Since 2021, Core Web Vitals have been part of Google's page experience signals, which directly influence search rankings. Sites that pass all three Core Web Vitals thresholds may receive a ranking boost, while sites with poor performance can be penalised, particularly on mobile.

Beyond rankings, speed affects user behaviour. Research shows that 53% of mobile users abandon sites that take longer than 3 seconds to load, and each additional second of load time reduces conversions by an average of 7%. Improving your PageSpeed score is not just about SEO — it directly impacts bounce rate, user engagement, and revenue.