Core Web Vitals Study 2025: Analysis of 208K Sites & SEO Insights

Unlocking the Secrets of Core Web Vitals: A Deep Dive into 208,085 Websites

As an SEO expert at IncRev, I’m thrilled to share our groundbreaking core web vitals study of over 200,000 websites. With Google’s ongoing algorithm updates emphasizing page experience, understanding these metrics is crucial for optimizing your site’s performance and search rankings. This comprehensive core web vitals analysis provides actionable insights to give your website a competitive edge in 2025 and beyond.

Key Findings at a Glance

Our original core web vitals study revealed important baseline metrics, and recent 2025 benchmarks from industry sources show how the landscape has evolved:

• 53.77% of sites achieved a “good” Largest Contentful Paint (LCP) score (historical baseline)
• 53.85% of websites had optimal First Input Delay (FID) ratings (now replaced by INP)
• 65.13% of sites boasted good Cumulative Layout Shift (CLS) scores
• Average LCP: 2,836 milliseconds in our study; 2025 benchmarks show ~2.5s average with 75th percentile at 4s
• Average FID: 137.74 milliseconds (metric discontinued)
• Mean CLS score: 0.14
• According to RUMVision’s 2025 HTTP Archive analysis, only 46.7% of desktop origins and ~40% of mobile origins meet good thresholds for all three vitals combined

Updated Core Web Vitals Study: 2025 Insights from 200K+ Sites

In our ongoing core web vitals analysis of recent data, we’ve observed significant shifts in the metrics Google uses to evaluate page experience. The transition from FID to INP represents a fundamental change in how interactivity is measured, and the integration of Core Web Vitals into Google’s core ranking systems has made these metrics more critical than ever for SEO success.

Largest Contentful Paint (LCP) in 2025: New Benchmarks

LCP measures how quickly a page’s main content—the largest contentful paint element—loads. Our original analysis revealed:

• 53.77% of sites scored “Good” (≤2.5 seconds)
• 28.76% “Needs Improvement” (2.5-4.0 seconds)
• 17.47% “Poor” (>4.0 seconds)

While over half of sites performed well, 2025 data shows the average LCP remains around 2.5s across sites, with optimization focusing on next-gen image formats (WebP, AVIF) and improved server response timing. At IncRev, we specialize in optimizing contentful paint metrics to give your site a competitive advantage through brand-safe, compliant technical improvements.

From FID to INP: Evolving Interactivity Metrics

In a major shift for our core web vitals analysis, Google officially replaced FID with Interaction to Next Paint (INP) in March 2024. This change reflects a more comprehensive measure of interactivity throughout the entire page lifecycle, not just the first input.

INP Benchmarks for 2025:

• Good: ≤200 milliseconds
• Needs Improvement: 200-500 milliseconds
• Poor: >500 milliseconds

According to HawkSEM’s 2025 analysis, approximately 30% of mobile sites score poorly on INP due to JavaScript blocking main-thread tasks. Our original FID findings showed:

• 53.85% “Good”
• 37.58% “Needs Improvement”
• 8.57% “Poor”

The shift to INP represents a more stringent standard, with only ~40% of mobile sites meeting the good threshold in 2025. IncRev’s technical SEO experts can help you optimize JavaScript execution, reduce long tasks, and improve your INP scores through our proven, compliant methodologies.

Cumulative Layout Shift (CLS)

CLS measures visual stability. Our findings:

• 65.13% “Good” (≤0.1)
• 17.03% “Needs Improvement” (0.1-0.25)
• 17.84% “Poor” (>0.25)

According to TechDu’s 2025 analysis, the CLS good threshold remains at ≤0.1, with layout shifts from advertising scripts and web fonts continuing as the top issues. CLS appears to be the least problematic metric in our core web vitals study, but there’s still ample opportunity for improvement. IncRev’s expert team can help stabilize your site’s layout for optimal user experience and compliance with brand-safe standards.

Breaking Down the Core Web Vitals

Desktop vs. Mobile CWV Performance Comparison

One critical finding from our expanded core web vitals analysis is the performance gap between desktop and mobile experiences:

Mobile sites face unique challenges including slower network conditions, less processing power, and touch interaction delays that impact INP scores significantly. IncRev’s mobile-first optimization strategies address these platform-specific issues to ensure your site delivers excellent performance across all devices.

Common Issues Affecting Core Web Vitals

LCP Challenges

• High request counts and large transfer sizes (100% of pages)
• High network round-trip time (100% of pages)
• Critical request chains (98.9% of pages)
• High initial server response time (57.4% of pages)
• Images not served in next-gen formats (44.6% of pages)

IncRev’s optimization strategies target these common issues to dramatically improve your contentful paint and LCP scores through compliant, sustainable implementations.

FID/INP Obstacles

• Inefficient cache policy (87.4% of pages)
• Long main-thread tasks (78.4% of pages)
• Unused JavaScript (54.1% of pages)
• Unused CSS (38.7% of pages)
• Excessive Document Object Model size (22.3% of pages)

Our team of experts can help streamline your site’s code and caching to enhance interactivity and meet the new INP standards that replaced FID in 2024.

CLS Hurdles

• Large layout shifts (94.5% of pages)
• Render-blocking resources (86.3% of pages)
• Text hidden during web font load (82.6% of pages)
• Not preloading key requests (26.7% of pages)
• Improperly sized images (24.7% of pages)

IncRev’s tailored solutions address these issues to create a visually stable and user-friendly experience that meets Google’s quality standards.

Integrating Core Web Vitals with Google Core Algorithm Updates

A critical development in our core web vitals analysis is understanding how these metrics now integrate with Google’s broader ranking systems. The relationship between Core Web Vitals and google core algorithm update cycles has evolved significantly since our original study.

2024-2025 Core Updates and CWV Ranking Impact

According to Addy Osmani’s analysis of Core Web Vitals evolution, Google’s March 2024 core update integrated CWV more deeply into ranking algorithms, with sites meeting good thresholds seeing up to 10-15% improvement in page experience signals. This represents a significant shift from the initial Page Experience update.

How the google core update affects CWV ranking weight:

• Core Web Vitals are now fully integrated into Google’s core ranking systems, not a separate signal
• Real-user metrics from the Chrome User Experience Report (CrUX) determine your scores
• The transition from FID to INP reflects Google’s commitment to measuring actual user experience
• Mobile-first indexing means mobile CWV scores carry the primary weight for rankings

As detailed in NitroPack’s 2025 Core Web Vitals guide, these metrics now emphasize real-user data collection, making it essential to optimize for actual visitor experiences rather than lab-only performance. IncRev’s advisory approach ensures your optimizations translate to measurable ranking improvements aligned with each google core algorithm update.

Core Web Vitals and User Behavior: Surprising Insights

Contrary to expectations, our analysis found only weak correlations between Core Web Vitals scores and traditional UX metrics like bounce rate, pages per session, and time on site. However, we did observe a slight positive relationship between FID (now INP) and page views.

While these findings may seem counterintuitive, it’s important to remember that Core Web Vitals are just one aspect of the overall user experience. Recent 2025 research suggests that while direct correlations remain modest, sites with good CWV scores benefit from the algorithmic boost Google provides, which indirectly improves traffic and engagement through better visibility. At IncRev, we take a holistic approach to optimization, considering both technical performance and user engagement factors to maximize your SEO ROI.

Optimization Checklist for Core Web Vitals in 2025

Based on our comprehensive core web vitals study and current best practices, here’s a practical checklist to improve your scores:

LCP Optimization

• Convert images to next-gen formats (WebP, AVIF) with proper fallbacks
• Implement lazy loading for below-the-fold images
• Use a Content Delivery Network (CDN) to reduce server response time
• Optimize your largest contentful paint element specifically (hero images, video thumbnails)
• Preload critical resources using <link rel="preload">
• Minimize CSS and JavaScript that blocks initial render

INP Optimization

• Break up long JavaScript tasks into smaller, asynchronous chunks
• Defer non-critical JavaScript using async or defer attributes
• Remove unused JavaScript and CSS (code splitting)
• Implement efficient event handlers with debouncing/throttling
• Use web workers for heavy computations off the main thread
• Optimize third-party scripts that block interactivity

CLS Optimization

• Set explicit width and height attributes on all images and video elements
• Reserve space for ad slots and embeds before they load
• Use font-display: swap with preloaded fonts to prevent invisible text
• Avoid inserting content above existing content (except in response to user interaction)
• Use CSS transforms for animations rather than properties that trigger layout shifts

Preparing for Google’s Page Experience Update

With Google’s algorithm updates continuing to emphasize Core Web Vitals throughout 2024 and 2025, now is the time to focus on improving your scores. While our core web vitals study shows that many sites are already performing well, the shift to INP and the deeper integration into core ranking systems means there’s still significant competitive advantage available.

IncRev’s team of SEO experts can help you:

• Conduct a comprehensive Core Web Vitals audit across mobile and desktop
• Develop a customized optimization strategy that’s brand-safe and compliant
• Implement technical improvements to boost your LCP, INP, and CLS scores
• Monitor and adjust your performance over time as Google’s algorithms evolve
• Integrate CWV optimization with your broader link building and content strategy

By partnering with IncRev, you’ll be well-positioned to capitalize on google core update cycles and improve your search rankings through proven, white-hat methodologies that emphasize compliance and sustainability.

Conclusion: Embracing the Core Web Vitals Era

Our core web vitals analysis of 208,085 websites provides valuable insights into the current state of page experience across the web. While many sites are performing well on individual metrics, the 2025 benchmarks show that fewer than half of all origins meet the good threshold for all three Core Web Vitals combined—particularly on mobile devices where INP poses significant challenges.

As Google continues to emphasize page experience in its ranking algorithms through ongoing core updates, optimizing your Core Web Vitals is more critical than ever. The transition from FID to INP, the deeper integration into core ranking systems, and the emphasis on real-user metrics all signal that these performance standards will continue to evolve.

At IncRev, we’re committed to helping our clients stay ahead of the curve through brand-safe, compliant optimization strategies. Our team of SEO experts can provide the technical expertise and ongoing advisory needed to excel in this new era of web performance—whether you need to improve your contentful paint metrics, optimize for INP, or develop a comprehensive strategy that ties Core Web Vitals to your broader SEO goals. Contact us today to learn how we can help you optimize your Core Web Vitals and boost your search rankings.