Your Google Lighthouse score (0–100) measures how fast, responsive and visually stable your site is. It matters because speed is a Google ranking factor and a direct conversion lever. Hitting Core Web Vitals targets — fast LCP, low INP, low CLS — is mostly about images, code and server discipline.
The Google Lighthouse speed score assesses how a page performs on loading speed, interactivity and visual stability, on a scale of 0–100. A higher score means a faster, smoother experience. Here's why it matters and how we hit it.
Why the score matters
- Users. Faster pages reduce bounce rates and keep people engaged.
- Rankings. Google uses page speed and Core Web Vitals as ranking factors, especially under mobile-first indexing.
- Conversions. Faster sites convert better — speed is a revenue lever, not just a vanity metric.
Core Web Vitals, in plain English
Lighthouse rolls up into three real-world metrics Google actually cares about:
- LCP (Largest Contentful Paint) — how quickly the main content appears. Target: under 2.5s.
- INP (Interaction to Next Paint) — how responsive the page feels when you tap or click. Target: under 200ms.
- CLS (Cumulative Layout Shift) — how much the layout jumps around as it loads. Target: under 0.1.
How we hit 90+ on mobile
- Images — modern formats (WebP/AVIF), correct sizing, and lazy loading below the fold.
- Code — minification, code splitting, and shipping as little JavaScript as possible. We server-render content so it's in the HTML, not hydrated late.
- Caching & delivery — browser caching for static assets and a CDN so files load from close to the user.
- Server — fast response times and efficient queries.
- Fonts — self-hosted and preloaded, so text appears immediately.
The link to SEO
Performance is part of technical SEO. A fast, stable, server-rendered page is easier for Google to crawl and rank — and easier for AI answer engines to read and cite. Speed isn't a nice-to-have you bolt on at the end; it's a foundation you build in from the start.
Want a site that's fast and findable? See how we approach AI web development, or book a call.
Frequently asked questions
Aim for 90+ on mobile across Performance, Accessibility, Best Practices and SEO. Mobile is what matters most because Google uses mobile-first indexing and most traffic is mobile. A green score on a mid-range Android over 4G means the site feels instant for everyone else.
Three real-world speed metrics Google uses: Largest Contentful Paint (how fast the main content loads, target under 2.5s), Interaction to Next Paint (responsiveness, target under 200ms) and Cumulative Layout Shift (visual stability, target under 0.1).
Yes. Page experience and Core Web Vitals are confirmed Google ranking signals, and faster pages also reduce bounce and lift conversions — so speed pays off twice.