Core Web Vitals and UX Signals: Their Role in SEO Success in 2025

In 2025, SEO is no longer just about keywords and backlinks. The overall experience your website delivers—how fast it loads, how stable it feels, and how users interact with it—now plays a critical role in your search rankings. Google’s Core Web Vitals and broader user experience (UX) signals are at the centre of this evolution.

This article explores what Core Web Vitals are, why they matter for SEO, and how UX signals like mobile usability, interactivity, and page stability directly impact your site’s performance in Google Search. We’ll also provide practical tools and tips to improve your scores—while following Google’s E-E-A-T principles: Experience, Expertise, Authoritativeness, and Trustworthiness.

What Are Core Web Vitals?

Core Web Vitals are a set of specific metrics that Google uses to evaluate page experience. These metrics reflect real-world user interactions and are part of Google’s overall ranking algorithm.

As of 2024, Core Web Vitals include:

1. Largest Contentful Paint (LCP):
   Measures loading performance. It tracks how long it takes for the largest visual element (like a hero image or heading) to appear.
   
   • ✅ Good: ≤ 2.5 seconds
     
2. Interaction to Next Paint (INP):
   Replaces First Input Delay (FID) in 2024. INP measures the time from a user’s interaction (click, tap, or keyboard input) to when the screen responds.
   
   • ✅ Good: ≤ 200 milliseconds
     (Google, 2024)
     
3. Cumulative Layout Shift (CLS):
   Measures visual stability. It tracks unexpected layout shifts (like buttons moving while the page loads).
   
   • ✅ Good: ≤ 0.1
     (Google Developers, 2024)
     

Together, these metrics help Google determine whether users have a smooth and satisfying experience on your website.

Why Core Web Vitals Matter for SEO

Since 2021, Google has integrated Core Web Vitals into its ranking algorithm as part of the Page Experience Update. In 2025, these signals carry even more weight due to increased competition and user expectations.

How Core Web Vitals Affect Rankings:

• Better scores = Higher rankings (especially for mobile users)
  
• Poor scores = Lower visibility, higher bounce rates, and lost traffic
  

According to Deloitte and Google (2023), mobile users are 24% less likely to abandon pages that load in under 2 seconds—and conversion rates improve by up to 20% when performance improves by just 0.1 seconds.

In short: Performance impacts both rankings and revenue.

UX Signals Beyond Core Web Vitals

While Core Web Vitals are technical, user experience (UX) signals go beyond the metrics. Google also considers:

1. Mobile-Friendliness
   Your site must be usable and readable on smartphones and tablets.
   
   • Use responsive design
     
   • Avoid small fonts and tap targets
     
   • Test with Google’s Mobile-Friendly Test
     
2. HTTPS Security
   Secure sites (those using HTTPS) are trusted and ranked higher.
   
   • Obtain an SSL certificate
     
   • Redirect HTTP traffic to HTTPS
     
3. No Intrusive Interstitials
   Pop-ups that block content, especially on mobile, are penalised.
   
   • Use pop-ups responsibly
     
   • Avoid full-screen interstitials
     
4. Safe Browsing
   Sites flagged for malware, phishing, or misleading content are downgraded.
   
   • Monitor in Google Search Console
     
   • Fix security issues immediately
     

These UX signals are part of the Page Experience framework and directly impact how Google evaluates your website (Google Search Central, 2024).

Tools to Measure Core Web Vitals

Here are the top tools recommended by SEO professionals and Google:

Tool	Description	Link
PageSpeed Insights	Measures Core Web Vitals and offers optimisation tips
Google Search Console	Monitors real-world user data for all indexed pages
Lighthouse	Runs lab-based audits of performance and SEO
WebPageTest	Advanced testing with visual load waterfalls
Chrome User Experience Report	Aggregated real-user data (field data) for millions of websites

How to Improve Each Core Web Vital

1. Improving LCP (Load Speed)

• Compress images using tools like TinyPNG
  
• Use faster hosting or a CDN (e.g., Cloudflare)
  
• Minimise render-blocking JavaScript and CSS
  

2. Reducing INP (Interaction Delay)

• Use efficient JavaScript frameworks (avoid overloading the DOM)
  
• Defer non-critical scripts
  
• Optimise for mobile tap targets and responsive interactivity
  

3. Reducing CLS (Visual Stability)

• Always include image size attributes
  
• Avoid inserting new content above existing elements
  
• Reserve space for dynamic content (ads, banners, etc.)
  

Improving your site across these metrics can lead to measurable gains in ranking, engagement, and conversion rates.

E-E-A-T: Why It Still Matters for UX

While Core Web Vitals focus on technical performance, Google also expects websites to show trust, credibility, and expertise.

How to Enhance E-E-A-T Through UX:

• Include clear author bios and credentials
  
• Publish original content based on real-world experience
  
• Use https, a visible contact page, and real business details
  
• Reference reliable sources and update content regularly
  

These elements signal to users and Google that your site is both useful and safe.

Core Web Vitals for Different Industries

Not all websites have the same speed or interaction needs. But all benefit from optimising user experience:

Industry	UX Focus Area
eCommerce	Fast LCP, stable layout for product pages, secure checkout
Blogs	Mobile readability, ad stability (CLS), fast load
Healthcare	Trust (E-E-A-T), secure (HTTPS), low INP for tools
Finance	Fast + stable forms, no intrusive interstitials, good CLS
Education	Video stability, structured layout, responsive design

Knowing your industry’s needs helps you prioritise the right UX optimisations.

UX Mistakes That Harm SEO

Avoid these common issues:

• Uncompressed images and large files
  
• No mobile responsiveness
  
• Shifting layouts and annoying pop-ups
  
• Slow server response times
  
• Poor navigation or broken links
  

Each of these can harm your Core Web Vitals scores and push your site down in rankings.

What’s New in 2025: INP and AI Evaluation

In 2024, INP (Interaction to Next Paint) officially replaced FID as a Core Web Vital. INP offers a better picture of how users actually experience responsiveness.

In 2025, Google is also experimenting with AI-based evaluations of page experience, using its Gemini models to interpret engagement and layout.

This means that your site must be both:

• Technically excellent (fast, stable, responsive)
  
• User-friendly and trustworthy (E-E-A-T compliant)
  

References

Deloitte & Google. (2023). Milliseconds make millions: Why mobile speed can be a business multiplier. https://www.thinkwithgoogle.com/marketing-strategies/app-and-mobile/mobile-page-speed-load-time-statistics/

Google. (2024). Interaction to Next Paint (INP). https://web.dev/articles/inp

Google Developers. (2024). Core Web Vitals update. https://developers.google.com/search/blog/2024/page-experience-updates

Google Search Central. (2024). Page experience and site ranking. https://developers.google.com/search/docs/appearance/page-experience

Schema.org. (n.d.). FAQPage structured data. https://schema.org/FAQPage