Core Web Vitals

What are Core Web Vitals?

Core Web Vitals are a set of specific factors that Google considers important in a webpage’s overall user experience. They are part of Google’s Web Vitals initiative, which aims to provide unified guidance for quality signals that are essential to delivering a great user experience on the web. Core Web Vitals focus on three aspects of the user experience: loading performance, interactivity, and visual stability of a page. These metrics are intended to help website owners, developers, and SEO professionals understand how users perceive the experience of a specific page and how to improve it.

Components of Core Web Vitals

Core Web Vitals consist of three main metrics:

  1. Largest Contentful Paint (LCP): Measures loading performance. To provide a good user experience, LCP should occur within 2.5 seconds of when the page first starts loading.
  2. First Input Delay (FID): Measures interactivity. Pages should have an FID of 100 milliseconds or less to ensure interactions feel fluid.
  3. Cumulative Layout Shift (CLS): Measures visual stability. To ensure a good user experience, pages should maintain a CLS of 0.1 or less.

Why Core Web Vitals Matter

  • User Experience: They directly impact how users perceive the speed, responsiveness, and stability of a page, influencing satisfaction and engagement.
  • SEO: Google has incorporated Core Web Vitals into its ranking criteria, making them a significant factor for search engine optimization.
  • Conversion Rates: Improvements in these areas can lead to better conversion rates, as users are more likely to engage with a site that loads quickly, responds promptly to inputs, and doesn’t shift layout unexpectedly.

Measuring Core Web Vitals

Google provides several tools to measure and report on Core Web Vitals, including:

  • PageSpeed Insights: Offers both lab and field data about a page’s performance and specific recommendations for improvement.
  • Chrome User Experience Report (CrUX): Provides real-world user experience insights from millions of websites, which can be accessed through BigQuery or tools like CrUX Dashboard and PageSpeed Insights.
  • Web Vitals Extension: A Chrome extension that provides instant feedback on Core Web Vitals as you browse the web.

Improving Core Web Vitals

Improving Core Web Vitals requires a targeted approach to addressing each specific metric:

  • Optimizing for LCP: Ensure fast server response times, adopt next-gen formats for images and videos, and remove any unnecessarily third-party scripts.
  • Improving FID: Minimize JavaScript execution time, split long tasks into smaller ones, and use a web worker if applicable.
  • Enhancing CLS: Use size attributes for images and videos to prevent layout shifts, and avoid inserting new content above existing content unless in response to a user interaction.

Real-world Application and Impact

Improving Core Web Vitals has become a priority for many organizations. For example, a leading e-commerce site found that optimizing images and reducing JavaScript execution times cut its LCP in half, leading to a significant increase in customer engagement and sales. Similarly, a news website reduced its CLS by ensuring ads and images had explicit width and height attributes, resulting in a decrease in bounce rates and an increase in page views per session.


Core Web Vitals are essential metrics for anyone involved in web development and digital marketing, as they directly impact user experience and SEO. By focusing on optimizing these vital aspects of web performance, businesses can improve their website’s visibility, user satisfaction, and ultimately, their bottom line. Regularly measuring and enhancing Core Web Vitals should be an integral part of any web optimization strategy.

Nedim Mehic

Nedim is a senior technical SEO specialist, and the co-founder of Beki AI. On the Beki AI blog, we share new and innovative strategies to SEO and content marketing.

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