Core Web Vitals are the metrics Google uses to measure real user experience, and they feed into ranking. Optimising LCP, CLS and INP makes a site faster and more pleasant to use — and turns the metrics green.
The three key metrics
- LCP (Largest Contentful Paint) — how fast the main content appears;
- CLS (Cumulative Layout Shift) — layout stability (nothing jumps around);
- INP (Interaction to Next Paint) — how fast the page responds to actions.
How LCP is improved
Optimising the main image or banner, preloading critical resources, a fast server (TTFB), and removing render-blocking CSS and JS.
How CLS is improved
Reserving space for images and ads (width/height), avoiding insertions that shift content, and loading fonts correctly.
How INP is improved
Reducing heavy JavaScript, breaking up long tasks, and removing surplus third-party scripts that block the main thread.
The result
Green Core Web Vitals improve both user behaviour metrics (fewer bounces) and search positions.
Common questions
Do you check against real data?
Yes, both field data (CrUX) and lab data (Lighthouse).
Can CLS caused by ads be fixed?
Yes, by reserving space for the blocks.
Without changing the design?
For the most part, yes.
Metrics in the red? I will optimise Core Web Vitals into the green.
