Core Web Vitals: why speed decides your Google ranking
Why speed isn't a detail
Google ranks websites not just by content but by user experience. The most important measurable signals for that are the Core Web Vitals. A fast page ranks better, keeps visitors longer and converts more — a slow one loses on all three. Speed isn't a technical footnote; it's directly tied to your revenue.
The three metrics that matter
- LCP (Largest Contentful Paint). How quickly the largest visible content loads. Target: under 2.5 seconds.
- INP (Interaction to Next Paint). How smoothly the page responds to clicks and input. Target: under 200 milliseconds.
- CLS (Cumulative Layout Shift). How much elements "jump" while loading. Target: under 0.1.
The most common drags — and what fixes them
- Huge images. Unoptimised images are the classic culprit. Modern formats (WebP/AVIF), fixed dimensions and lazy loading solve it. That's exactly what a component like
next/imageis built for. - Too much JavaScript. Every unnecessary script delays interactivity. Less is more here — and server-side rendering helps further.
- Shifting layout. When images and ads have no reserved size, content jumps around. Fixed dimensions prevent it.
- Slow hosting. Time to First Byte counts. Modern hosting with a CDN and edge caching makes a noticeable difference.
Why the right stack is half the battle
Performance can be fought for after the fact — or built in from the start. A modern web project on Next.js ships server-side rendering, automatic image optimisation and clean code-splitting out of the box. That's far cheaper than repairing a slow site later.
How to approach it
Measure first — with PageSpeed Insights or Search Console — then prioritise the biggest levers. Often a few changes deliver the largest jump.
Want to know where your site stands and what's worth doing? Drop us a line — we'll take a look and tell you honestly where the biggest potential is.