A slow website doesn't just feel frustrating to use — it actively drives potential clients away and damages your ranking on Google. The research is clear, the impact is measurable, and the good news is that most speed problems are entirely fixable.
The numbers that should concern you
Studies consistently show that page speed has a dramatic effect on visitor behaviour. A website that loads in one second converts three times better than one that takes five seconds. For every additional second of load time, you can expect to lose roughly 10% of your visitors — before they've seen a single word of your content.
Amazon once calculated that every 100ms of additional load time cost them 1% in sales. If that's true for the world's largest retailer, the proportional impact on a small business is just as significant.
Why page speed affects your Google ranking
In 2021, Google introduced "Core Web Vitals" as an official ranking factor. These are a set of measurements that assess how fast and stable a page feels to a real user — how quickly content appears, how quickly it becomes interactive, and whether elements jump around as the page loads.
A site that scores poorly on Core Web Vitals will rank lower than a comparable site that scores well. This means a slow site doesn't just frustrate the visitors who do find you — it means fewer people find you in the first place.
How to test your website speed
Two free tools that give you an immediate, accurate picture:
- Google PageSpeed Insights (pagespeed.web.dev) — Google's own tool, scores your site out of 100 and lists specific issues to fix
- GTmetrix (gtmetrix.com) — more detailed breakdown, shows a waterfall of every element loading and how long each takes
Run both on your site's homepage and your most important page (usually your services or contact page). A score below 70 on mobile PageSpeed Insights indicates a problem that's likely affecting your business.
The most common causes of slow websites
Unoptimised images
This is the single biggest culprit in most slow websites. A photo straight from a camera or stock site can be 5–10MB. The same image, properly compressed and resized for web, should be under 200KB. That's a 25–50x difference in file size — and it makes a huge difference to load times.
Too many plugins
WordPress sites in particular can accumulate plugins over time — each one adding its own CSS, JavaScript, and database queries. A site with 30 active plugins is almost always slower than it needs to be.
Cheap shared hosting
Budget hosting puts your website on a server shared with hundreds or thousands of other sites. When those sites get busy, yours gets slower. Upgrading to a better hosting provider is often the fastest way to improve your site speed with minimal technical work.
No caching
Caching stores a version of your pages so they don't have to be rebuilt from scratch every time someone visits. Without it, your server does unnecessary work on every single page load.
Render-blocking scripts
Scripts and stylesheets that load before your page content is visible can delay how quickly visitors see anything at all — even if the page itself isn't particularly large.
What good looks like
- Mobile PageSpeed score of 80 or above
- Page loads in under 2.5 seconds on a typical mobile connection
- Core Web Vitals all showing green in Google Search Console
- Total page size under 1MB for a typical brochure page
Given my background in IT infrastructure, performance is something I take seriously on every project I build. Fast, well-optimised sites aren't complicated to achieve — they just require the right decisions at the right points in the build process. If you'd like your site audited for speed issues, get in touch — I offer standalone speed audits from £99.