Core Web Vitals refers to a set of specific metrics used by Google Lighthouse (included in DevTools) and PageSpeed Insights to measure and evaluate page loading speed, interactivity, and performance.

Metrics include:

  • Largest Contentful Paint (LCP) – measures loading performance
  • First Input Delay (FID) – measures interactivity
  • Cumulative Layout Shift (CLS) – measures visual stability
  • Real World User Measurement – focuses on real user experience

While acting on Core Web Vitals requires coding knowledge, site owners can simply choose pre-built web designs (such as WordPress or Drupal themes) that are already optimized.

The key is that the metrics focus attention on aspects of site performance that impact page experience, which is a Google ranking factor.