Core Web Vitals: Why Website Speed Affects Sales and Rankings
Slow websites lose visitors before they see your offer. Learn what Core Web Vitals measure and the fixes that make the biggest difference.
Every second a page takes to load gives visitors a reason to leave. Speed affects your conversion rate, your ad costs and your search rankings. Google measures user experience with a set of metrics called Core Web Vitals.
The three Core Web Vitals
| Metric | What it measures | Good score |
|---|---|---|
| Largest Contentful Paint (LCP) | How quickly the main content appears | 2.5 seconds or less |
| Interaction to Next Paint (INP) | How quickly the page responds to taps and clicks | 200 ms or less |
| Cumulative Layout Shift (CLS) | How much the layout jumps while loading | 0.1 or less |
How to check your scores
Run your pages through PageSpeed Insights and look at the Core Web Vitals report in Google Search Console. Focus on mobile scores first, because that is where most visitors are and what Google primarily evaluates.
The fixes that usually matter most
Images
- Resize images to the size they are displayed.
- Use modern formats such as WebP or AVIF.
- Lazy-load images below the fold, but not the main hero image.
- Always set width and height to prevent layout shifts.
Hosting and caching
Cheap shared hosting is often the biggest bottleneck. Good hosting, page caching and a CDN can transform load times.
Scripts and plugins
Every chat widget, slider, tracking script and plugin adds weight. Remove what you do not use and delay non-essential scripts.
Fonts
Limit the number of font families and weights, preconnect to font servers and use font-display: swap.
Speed and conversions
Faster pages keep more visitors, which means more enquiries from the same traffic and better returns on ad spend. Speed work often pays for itself.
Every site built by our web team is tuned for Core Web Vitals before launch. Want to know where you stand? Request a free website audit.
Frequently asked questions
Do Core Web Vitals directly affect rankings?
They are part of Google’s page experience signals. Content relevance matters more, but when pages are similar, better experience can help, and it always helps conversions.
Why is my mobile score lower than desktop?
Mobile tests simulate slower devices and networks, so heavy images and scripts have a bigger impact. Optimise for mobile first.