What are Core Web Vitals?
Core Web Vitals are a set of specific metrics developed by Google to measure the user experience of a webpage, with a focus on loading performance, interactivity, and visual stability. These vitals are part of Google’s broader “Page Experience” signals and are considered ranking factors.
The three key Core Web Vitals are:
- Largest Contentful Paint (LCP): Measures loading performance. Aim for under 2.5 seconds.
- First Input Delay (FID): Measures interactivity. Aim for under 100 milliseconds.
- Cumulative Layout Shift (CLS): Measures visual stability. Aim for a score below 0.1.
Why Core Web Vitals Matter
Core Web Vitals directly affect how users experience your website. Pages that load quickly, respond smoothly, and remain visually stable provide better usability, reduce bounce rates, and improve engagement, all of which contribute to stronger SEO performance.
Google uses these metrics as part of its ranking algorithm, meaning that websites with poor scores may be disadvantaged in search results.
Benefits of improving Core Web Vitals include:
- Higher rankings in search results
- Better user satisfaction and trust
- Increased conversions and time on site
- Lower bounce rates
Example in Use
If a blog post’s main image takes 5 seconds to load (poor LCP), and the layout shifts when an ad loads (high CLS), it may frustrate users and cause them to leave the page. Optimising the image size, reducing third-party scripts, and reserving space for dynamic elements can all improve Core Web Vitals scores.
Related Terms
- Page Speed
- Mobile-Friendly Design
- User Experience (UX)
- Technical SEO
- Google Search Console