What Are Core Web Vitals and How to Improve Them

Core Web Vitals are a set of real-world measurements Google uses to judge how good your page feels to actual users — how fast it loads, how quickly it responds, and how stable it is as it appears. Because they influence search rankings, they are worth understanding and improving.

The three metrics, in plain English

• LCP (Largest Contentful Paint) — how long until the main content appears. Measures loading speed. Aim for under 2.5 seconds.
• INP (Interaction to Next Paint) — how quickly the page responds when someone taps or clicks. Measures responsiveness.
• CLS (Cumulative Layout Shift) — how much the layout jumps around as it loads. Measures visual stability.

How to improve LCP (loading)

Speed up what paints first: optimise images, enable caching, improve server response with OPcache, and consider a CDN.

How to improve INP (responsiveness)

Heavy JavaScript is the usual culprit. Reduce and defer scripts, remove unused code, and avoid piling on plugins that add their own scripts to every page.

How to improve CLS (stability)

Layout shift comes from elements loading without reserved space. Set width and height on images, reserve space for ads and embeds, and avoid inserting content above what the visitor is already reading.

Measuring your vitals

PageSpeed Insights reports your Core Web Vitals — see improving your PageSpeed score — and Google Search Console has a dedicated Core Web Vitals report showing real visitor data.

Frequently asked questions

Do Core Web Vitals really affect my ranking?

They are a ranking factor, though content relevance still matters most. Think of good vitals as a tie-breaker and, more importantly, a better experience that keeps visitors from leaving.

My lab test passes but Search Console says I fail.

Lab tools simulate one visit; Search Console uses real-user data across many devices and networks. Trust the field data in Search Console and improve the metrics it flags.

What replaced the old FID metric?

INP (Interaction to Next Paint) has replaced the older First Input Delay as the responsiveness metric, giving a fuller picture of how snappy a page feels throughout a visit.