If you run a restaurant, a clinic, a shop or any local business in Spain, your website is your cheapest and hardest-working salesperson: open 24 hours a day, 365 days a year, talking to potential customers while you sleep. The problem is that most local business websites fail Google's audit — and that has direct consequences on clients and revenue.
In this article I explain what Google measures with its Lighthouse tool, why 100/100 across all 4 metrics matters more than you think, and how a well-built website can be the difference between ranking first on Google or being invisible.
What is Google Lighthouse and why should you care?
Lighthouse is Google's official tool for auditing website quality. It analyses your page and returns a score from 0 to 100 in four categories:
- Performance: How fast does your website load?
- Accessibility: Can all your customers use it?
- Best Practices: Is it secure and technically correct?
- SEO: Is it optimised so Google understands it?
Check your website score in under 1 minute
Before reading on, here's a quick exercise: check your own website score right now. No installation needed, no technical knowledge required.
- Open a new tab and go to pagespeed.web.dev — Google's free tool
- Type your website address (for example: myrestaurant.com)
- Make sure «Mobile» is selected at the top
- Click the «Analyze» button and wait around 20 seconds
- You'll see 4 coloured circles — those are your real results
The colour code is straightforward: green (90-100) = good, orange (50-89) = needs improvement, red (0-49) = serious problem. If you see any orange or red, you're losing customers without knowing it — every extra second of load time and every lost SEO point has a direct cost in bookings and calls you never receive.
⚡ Important: always test on mobile
70% of local searches happen from a phone. Google uses the mobile version of your website to decide your ranking — if your site is slow on mobile, it penalises you even if it works perfectly on desktop. Always select «Mobile» before analysing.
Got your results? Now let me explain what each metric means and why it matters for your business.
Lighthouse isn't just a tool for developers. It's the same criteria Google uses to decide who appears at the top of search results. If your site fails, Google knows — and penalises you, even if it doesn't say so explicitly.
📊 Real data
Websites that load in under 1 second convert up to 3× more than those taking 5 seconds. Every second of delay reduces conversions by 7% on average. (Source: Think with Google / Deloitte, 2019)
Performance: speed isn't a luxury, it's money
Web performance is the metric with the most direct impact on local businesses. When someone searches «restaurant in Granada» on mobile, they have little patience. If your site takes more than 2–3 seconds to load, 53% of users leave before seeing it (Google, 2018).
A score of 100 in performance means your website:
- Loads the first visible content in under 1 second
- Is interactive in under 2 seconds
- Produces no visual shifts while loading (CLS = 0)
- Serves images in modern formats (WebP, AVIF) at the exact displayed size
For a local business this translates to: fewer bounces, more time on site and more enquiries or bookings. Google also factors this into its local ranking algorithm (Core Web Vitals since 2021).
Accessibility: more customers and fewer legal risks
Web accessibility is the most ignored metric and, paradoxically, the one that can cost you the most potential customers. In Spain there are over 3.8 million people with some form of visual or motor disability. If your website doesn't meet WCAG 2.1 criteria, you're shutting the door on that market.
A score of 100 in accessibility means:
- All text has sufficient contrast against the background (minimum 4.5:1 ratio)
- Images have descriptive alternative text
- The site is navigable by keyboard and screen readers
- Forms are correctly labelled
- Buttons have minimum tappable sizes on mobile
Furthermore, Royal Decree 1112/2018 in Spain increasingly requires web accessibility from businesses. An accessible website isn't just ethical — it's good business and, in some cases, a legal obligation.
Best Practices: security and trust for your customers
The best practices category audits the technical hygiene of your website. It includes:
- Use of HTTPS (secure connection)
- Not loading JavaScript libraries with known vulnerabilities
- Images with correct proportions
- No errors in the browser console
- Compatibility with modern browser standards
A score of 100 here tells Google (and your customers) that your website is built with care. Modern browsers warn users when a site isn't secure — and that warning is enough to lose the sale at the most critical moment.
Technical SEO: let Google find you before your competition
Technical SEO is the foundation everything else rests on. Lighthouse audits that your website has:
- Unique and descriptive
titleandmeta descriptiontags - Correct heading structure (H1 → H2 → H3)
- Descriptive link text (not «click here»)
- XML sitemap and well-configured robots.txt
- Hreflang tags if you have multi-language versions
- Structured data (Schema.org) for local businesses
For a local business in Granada, Seville or Madrid, having technical SEO at 100 is the starting point. Without this foundation, the content you publish and the backlinks you acquire will have far less effect.
💡 Did you know?
Google has used Core Web Vitals (part of the performance score) as a ranking factor since May 2021. A website that scores poorly on performance can rank lower in results, even if its content is better than the competition's.
All 4 metrics together: the multiplier effect
The real value isn't in having one metric at 100. It's in the combined effect:
- Performance + SEO: Google ranks you higher AND users don't leave before seeing your business
- Accessibility + Best Practices: you project professionalism and trust, users convert more
- All 4 at 100: your website competes on equal terms with big brands that have entire teams behind them
Most local business websites in Spain score between 40 and 70 on mobile performance. Reaching 100 isn't just improving metrics — it's leaving all your local competition behind on a key Google criterion.
100/100 in practice: how it's achieved
Getting all 4 metrics to 100 isn't magic — it's precise technical work. In my case, some of the key elements were:
- WebP images at the exact displayed size (not serving a 2000px image to display it at 400px)
- Minimal CSS and JavaScript: only the code used on each page, no unnecessary heavy libraries
- System fonts instead of external fonts that block rendering
- Static generation with Astro: pure HTML served from CDN, no server wait time
- Colour contrast validated element by element using the WCAG formula
- Correct heading hierarchy across all pages (H1 → H2, no skipped levels)
- Schema.org for professional profile, articles and breadcrumbs
The result is a website that loads in 0.3s for the first visible content and 0.4s for the main element — measured on mobile devices with simulated 4G connection.
What does this mean for your business?
If you have a restaurant, a dental clinic, a hairdresser or any local business, a website with these scores gives you:
- ✅ More visibility on Google Maps and local search
- ✅ Lower cost per click on Google Ads (Quality Score rewards speed)
- ✅ More conversions: visitors who arrive, stay and book
- ✅ Professional image that builds trust from the first second
- ✅ Regulatory compliance on accessibility
And above all: a real competitive advantage over most local businesses with slow, inaccessible or poorly mobile-optimised websites.
Frequently asked questions about Google Lighthouse
What is Google Lighthouse and what is it used for?
Google Lighthouse is Google's official web auditing tool. It analyses any page and returns a score from 0 to 100 across four categories: performance, accessibility, best practices and SEO. It's not just for developers — it's the same technical benchmark Google uses to evaluate the quality of your website when deciding where to rank it in search results.
Does my website's loading speed really affect my ranking on Google?
Yes, directly. Since May 2021, Google uses Core Web Vitals — metrics that measure real loading speed, interactivity and visual stability — as a ranking factor. A slow website can rank lower than a competitor with better content just because it loads in 4 seconds instead of 1. For local businesses this is especially relevant: if someone searches «restaurant in Granada» on mobile and your site takes more than 3 seconds, they'll leave before seeing your business.
What does a score of 100 in accessibility mean?
It means your website is usable by all types of users: people with visual impairments, motor disabilities, older adults, users of screen readers. Concretely: all text has sufficient contrast against the background (minimum 4.5:1 ratio), images have descriptive alt text, forms are properly labelled and buttons are large enough to tap on mobile. In Spain, Royal Decree 1112/2018 increasingly requires accessibility from businesses — having a score of 100 is the easiest way to comply.
How do I know if my current website is failing Google Lighthouse?
It's straightforward: go to pagespeed.web.dev, enter your website's address, select «Mobile» and click Analyse. In about 20 seconds you'll see your four scores. If any circle is orange (below 90) or red (below 50), your website has problems that are directly affecting your visibility on Google and the number of enquiries you receive.
What is the difference between a Lighthouse score and real Google ranking?
Lighthouse measures the technical quality of your website — the foundation. Google ranking depends on many other factors: the quality of your content, the number of sites linking to you, how long users stay on your page. But Lighthouse is the starting point: without a solid technical score, the other factors work much less effectively. Think of it like a restaurant: the best menu in the world won't save you if the dining room is uncomfortable, dark and takes 10 minutes to bring each dish.
If you've heard about the Kit Digital programme and wonder whether the websites it funds actually achieve these technical standards, read: Kit Digital in Granada: what grants are available and why most websites don't generate clients →
🚀 Want to know how your website scores right now?
I can do a free audit of your current website and tell you exactly what score it gets and what can be improved. No commitment. Write to me here →
