Core Web Vitals: What are they and how to optimize them?

What are Core Web Vitals?

Google’s goal has always been to improve the user experience. That’s why it has developed tools like Pagespeed Insights, Lighthouse, AMP, and the Chrome UX Report. From that effort comes the Core Web Vitals initiative, which unifies key metrics to measure a website’s performance and usability.

A guide to improve your website

Core Web Vitals provide clear indicators to detect and improve usability and performance issues. At La Teva Web, we work with both technical teams and marketing/business professionals to help improve them.

Goals of Core Web Vitals

• Put the user first. Instead of measuring only page load times, Google now looks at what truly matters to users: when they see content, when they can interact, and whether the layout remains stable.
• Simplify. Google has reduced over 15 performance metrics down to 3 key and understandable indicators for all user profiles.
• Enable optimization. Tools like Lighthouse and PageSpeed Insights help detect issues and measure the impact of improvements.

The 3 Core Web Vitals metrics (updated)

LCP – Largest Contentful Paint

Measures how long it takes to load the largest visible content element on the page (image, video, text block...)

Good: < 2.5 s | Needs Improvement: 2.5–4 s | Poor: > 4 s

CLS – Cumulative Layout Shift

Measures visual stability. This reflects whether elements shift unexpectedly during load, which can lead to frustration or accidental clicks.

Good: < 0.1 | Needs Improvement: 0.1–0.25 | Poor: > 0.25

INP – Interaction to Next Paint

Since March 2024, INP has replaced FID as the official interactivity metric. It measures the longest response time of a user interaction (click, keypress, etc.) on the page.

Good: < 200 ms | Needs Improvement: 200–500 ms | Poor: > 500 ms

Want to know more? Read our dedicated article about INP (Interaction to Next Paint).

How to analyze and improve your metrics

Select representative URLs from your site (homepage, categories, product pages…). Then use tools like Lighthouse or PageSpeed Insights to assess performance. Also compare with competitors to prioritize efforts.

Key tips

• Use consistent testing environments (same browser, connection...)
• Combine real data (Search Console, Web Vitals extension) with simulated data (Lighthouse)
• Improving these metrics benefits both SEO and user conversion

Do Core Web Vitals affect SEO?

Yes. Since 2024, Core Web Vitals are part of Google’s real-world page experience signals and directly influence SEO rankings. A technically optimized site performs better in search, reduces bounce rates, and boosts conversions.

Summary

• Core Web Vitals focus on user experience, not just speed.
• They now include LCP, CLS, and INP (which replaces FID).
• Google uses them as ranking factors since 2024.
• Improving them has a direct impact on SEO and website performance.

Want to improve your Core Web Vitals? At La Teva Web, we specialize in technical SEO and performance optimization. Get in touch and let us help you create a faster, more usable, and better-ranking website.