Fixing Common Core Web Vitals Issues in 2025

Ritisha

May 27, 2025

Introduction

In 2025, staying competitive online is harder than ever. Search engines like Google are getting smarter, and they now look closely at how fast and smooth your website feels for users. That’s where Core Web Vitals come in. These are key performance measures that show how well your site loads, responds, and stays stable on the screen.

If you run a website—whether you’re a developer, SEO specialist, or part of a digital marketing agency—knowing how to fix Core Web Vitals problems is a must. It helps boost your Google rankings, keeps users happy, and increases your chances of making sales or getting leads. This guide will walk you through the most common Core Web Vitals issues and how to fix them using the latest best practices for 2025.

Understanding Google’s Core Web Vitals (2025 Update)

Core Web Vitals are a set of performance metrics established by Google to assess the quality of user experience on web pages. As of 2025, the three primary metrics remain as follows:

• LCP (Largest Contentful Paint): Evaluates loading performance. A score under 2.5 seconds is considered optimal.
• INP (Interaction to Next Paint): Replacing FID, this metric assesses responsiveness based on overall input latency. A good score is below 200 milliseconds.
• CLS (Cumulative Layout Shift): Measures visual stability during page load. A score below 0.1 is deemed acceptable.

In the past year, Google has introduced incremental updates to the way these metrics are measured. Most notably, INP has officially replaced FID as a Core Web Vital due to its more comprehensive evaluation of user interactions.

Furthermore, there is now a greater emphasis on real user monitoring (RUM) data over synthetic (lab-based) data, making tools such as the Chrome UX Report and Core Web Vitals report in Google Search Console increasingly significant for accurate performance assessments.

Common Core Web Vitals Issues in 2025

Many websites continue to fail Core Web Vitals assessments due to recurring and fixable problems. Let’s look at the most prevalent performance issues.

1. Slow LCP (Largest Contentful Paint)

• Unoptimized images
• Slow server response times
• Render-blocking resources

2. High CLS (Cumulative Layout Shift)

• Unstable images or ads
• Fonts loading late
• Dynamic content shifting elements on the page

3. Poor INP (Interaction to Next Paint)

• Heavy JavaScript execution
• Unoptimized third-party scripts
• Main-thread blocking

4. Failed Core Web Vitals Assessment

Often labeled in Search Console as “Core Web Vitals assessment has failed,” this issue typically arises from underperforming metrics across multiple page templates, particularly on mobile. It often indicates sitewide problems rather than isolated incidents.

How These Issues Affect SEO in 2025

Search engine optimization now extends beyond traditional elements such as keywords and backlinks. Google’s algorithm directly integrates Core Web Vitals into its ranking criteria. Substandard performance in these metrics can negatively impact search rankings, particularly in mobile search results. Websites with poor scores in metrics like LCP or INP often experience increased bounce rates and reduced user engagement, further exacerbating their SEO challenges.

For digital marketing agencies, these Google’s Web Vitals are now a fundamental component of technical SEO assessments. Performance optimization is recognized as a critical ranking factor, rather than being considered solely a user experience enhancement.

How to Run a Test For Core Web Vitals the Right Way

Before you fix issues, you need to measure them accurately. In 2025, these are the most reliable tools for Google’s Core Web Vitals testing:

PageSpeed Insights

• Uses both lab and field data
• Shows detailed breakdown for LCP, CLS, and INP

Chrome UX Report (CrUX)

• Public data set of real-user experiences

Lighthouse

• Simulated testing environment
• Useful for debugging

Core Web Vitals Chrome Extension

• Real-time assessment during browsing
• Useful for developers working on live sites

Search Console Web Vitals Report

• Aggregates field data from your site
• Highlights template-level problems

Best Practice: Combine field data from CrUX and Search Console with lab data from Lighthouse to get a full picture. This hybrid approach reveals both broad trends and actionable code-level issues.

Proven Techniques to Fix Core Web Vitals Issues

Let’s break down targeted strategies to improve each Core Web Vital.

Fixing Largest Contentful Paint (LCP)

Image Optimization

• Convert to next-gen formats like WebP or AVIF
• Use responsive image sizes
• Enable lazy loading outside the viewport

Reduce Server Response Time

• Use edge computing and CDNs
• Optimize TTFB (Time To First Byte)

Minimize Critical CSS and JS

• Eliminate unused code
• Inline critical styles
• Defer non-critical JavaScript

Preload Key Resources

• Fonts and hero images should be prioritized using rel=”preload”

Reducing Cumulative Layout Shift (CLS)

Define Dimensions

• Set width and height for images, videos, and iframes

Avoid Injecting Content

• Prevent layout shifts by not adding dynamic content above-the-fold after load

Font Optimization

• Use font-display: optional or swap
• Avoid FOIT (flash of invisible text)

Stabilize Ads

• Reserve space for ads using fixed dimensions or aspect-ratio containers

Improving INP (Interaction to Next Paint)

Reduce JavaScript Execution Time

• Break up long tasks
• Use async/defer for scripts

Implement Web Workers

• Offload heavy computation from the main thread

Optimize Input Latency

• Use event delegation
• Avoid large DOM trees

Code Splitting

• Load only necessary JS for the initial view

Fixing “Core Web Vitals Assessment Has Failed”

Isolate Problem Pages

Use Search Console to identify patterns across URLs

Prioritize Mobile Fixes

Google primarily uses mobile data for ranking

Address All Metrics

One poor metric can fail the entire assessment

Field Over Lab

Optimize for field data, as it’s what Google uses to assess pass/fail status

Advanced Core Web Vitals Optimization Tactics

If you’ve fixed basic issues but still lag behind competitors, consider these advanced Core Web Vitals strategies.

Use a Global CDN

Deliver assets from servers closer to users to reduce latency and improve LCP sitewide.

Prioritize Resource Hints

Add preconnect, dns-prefetch, and fetchpriority for faster loading of external assets.

JavaScript Frameworks

Modern frameworks like Next.js and Astro now have built-in Core Web Vitals enhancements like automatic image optimization, component lazy loading, and script prioritization.

Reduce Third-Party Impact

Audit third-party tools (e.g., chatbots, analytics, social embeds) and load them asynchronously or conditionally.

Lighthouse CI and Web Vitals Alerts

Integrate performance testing in your deployment pipeline using tools like Lighthouse CI and set alerts when metrics exceed thresholds.

Tools and Resources To Optimize Core Web Vitals

Google Search Console

Best source for real-user performance data

PageSpeed Insights

Actionable recommendations per URL

WebPageTest.org

In-depth analysis including filmstrips and waterfall charts

Core Web Vitals Chrome Extension

Instant feedback during browsing sessions

Lighthouse CI

Automates testing during development

Cloudflare / Fastly

CDN and edge platforms with optimization tools

NitroPack / WP Rocket (for CMS sites)

One-click performance optimization

Future of Core Web Vitals: What’s Next After 2025?

As Google’s algorithms evolve, page experience will expand to include:

• Accessibility scores
• Energy efficiency metrics
• AI-based UX predictions

Developers and SEO professionals should expect integration of Core Web Vitals into AI-assisted indexing and a stronger emphasis on accessibility-first design.

There’s also a shift toward predictive loading and personalized performance metrics, where scores vary based on user context (location, device, network).

Conclusion

Fixing Core Web Vitals in 2025 isn’t just a technical task—it’s a key part of improving your website’s speed, user experience, and search engine rankings. As more businesses compete online, making sure your site meets these standards is more important than ever.

Whether you manage your own website or work at a digital marketing agency, following the steps in this guide can help you improve your scores, boost your SEO, and stay aligned with Google’s latest rules.

If the process feels too complex or time-consuming, consider getting expert help. Hire Core Web Vitals Consultants who understand how to improve website speed, usability, and SEO based on the Core Web Vitals’ best practices for 2025.