Fixing Core Web Vitals Issues is no longer a difficult task. Google has identified the quality of user experience as crucial to the long-term success of any website, and Core Web Vitals (CWV) is a definitive benchmark for measuring this experience.
In this 2025 guide, we’ll look at why 54.2% of websites struggle to pass CWV, and how you can fix these common Core Web Vitals Issues to get your site to the good threshold of the 75th percentile.
This entire process is described in three steps: first running performance tests, then identifying specific CWV challenges, and finally implementing effective optimizations.
Core Web Vitals Issues: Understand What and Why?
Core Web Vitals is a set of three primary metrics that indicate the quality of the user experience on a website. Their main focus is:
- Loading Performance (LCP)
- Responsiveness (INP)
- Visual Stability (CLS)
Largest Contentful Paint (LCP) measures how long it takes for the main content of the page to load; a good score for this is 2.5 seconds. Interaction to Next Paint (INP) measures how quickly the page responds after user input (click/tap); Its good score is 200 ms.
Cumulative Layout Shift (CLS) measures how unexpectedly the content shifts while the page is loading, for which a good score is 1sec. Google says to pass these metrics at the 75% percentile, which means that 75%of your website visits should meet or exceed the recommended thresholds.
Testing Tools: Identify Core Web Vitals Issues Before starting optimization
It is important to know where and on which page the Core Web Vitals Issues are. Google’s official tools help you with this.
PageSpeed Insights (PSI) gives you both field data (real-world) and lab data for specific pages, as well as actionable advice in the Opportunities & Diagnostics sections.
The Google Search Console (GSC) – Core Web Vitals Report is best for viewing historical performance data for URLs across your site and identifying pages that need improvement.
Moreover, the Chrome User Experience Report (CrUX) dataset, a source of real-world user experience data, is available for in-depth analysis.
Major Core Web Vitals Issues and Their Causes
Core Web Vitals issues often stem from a few technical missteps commonly made. Fixing them requires a very good understanding of their causes. Causes of Large Contentful Paint (LCP) Issues LCP measures the loading performance of the main content, and the main culprits that make it worse than ideal are:
Slow Server Response Times and budget/shared hosting.
WordPress is a dynamic CMS, needing to fetch content from the database, and having a slow server increases Time to First Byte (TTFB), which causes delays in LCP.
Another major contributor is Render-Blocking JavaScript and CSS: scripts and stylesheets brought in by themes and plugins block page rendering until they have been fully processed, delaying the visibility of the main content.
Finally, unoptimized images adversely affect LCP because the large file size of high-resolution, unoptimized images takes more time to download and render, especially when 72% of mobile pages have an LCP element containing an image.
CLS can cause very frustrating user experience due to Cumulative Layout Shift (CLS) issues since content shifts unexpectedly. In fixing this, your focus should be on visual stability.
The first common issue is images without set dimensions. When width and height attributes are not defined for images, the browser cannot reserve space for the image.
The content suddenly shifts abruptly as soon as the image is loaded. Similarly, ads and dynamic content without reserved space also shift the layout; it is important to allocate placeholder space or fixed dimensions in advance for elements like ads, videos, or iframes. Unoptimized font delivery is also an issue with custom fonts
Late-loading custom fonts can cause FOIT (Flash of Invisible Text) or FOUT (Flash of Unstyled Text), and if the custom font is significantly different from the fallback font, the text layout gets reshuffled.
Causes of Interaction to Next Paint (INP) Issues
INP measures the responsiveness of a page, and its poor performance is often due to a blocked main thread. The first culprit is heavy JavaScript execution. Since JavaScript is single-threaded, extensive JS processing monopolizes the main thread, leaving it waiting for user input.
Poor resource prioritization is also an issue. If non-essential scripts are loaded before critical resources, the main thread is busy with unnecessary tasks, slowing down the page’s responsiveness.
Furthermore, excessive third-party scripts, such as analytics tools and widgets, increase latency by introducing large payloads and additional processing tasks. Finally, a large DOM size (more than 1,400 nodes) increases the rendering burden on the browser, leading to responsiveness issues. Optimization Checklist: Ways to Fix Core Web Vitals IssuesFixing Core Web Vitals issues requires a structured optimization plan. This checklist gives you specific steps to improve each metric.
LCP Optimization (Improve Loading Speed)To improve LCP, consider a hosting upgrade first. Shifting to premium dedicated or cloud hosting will significantly reduce TTFB and server response time.
The second step is to use a Content Delivery Network (CDN), so that data is delivered from the server closest to the user. For image optimization, use modern formats like WebP/AVIF, apply compression, and serve images tailored for the device using the srcset attribute. For code optimization, minify scripts and stylesheets, inline critical CSS in HTML, and use defer or async attributes for non-critical JS files
INP Optimization (Increase Responsiveness)Keeping the main thread free is essential for improving INP. Reduce unused CSS by minimizing unused CSS. Break up long JS tasks into smaller, asynchronous chunks (e.g., by using requestIdleCallback()) so that the main thread is free for user input.
Take performance to new heights The ultimate goal in trying to fix Core Web Vitals issues isn’t about getting a green tick on Google’s checklist; rather, it is to let your user get a better, smoother experience.
This top-notch user experience converts directly into increased conversion rates and low bounce rates. If you’re tired of managing all these technical optimizations yourself and are looking forward to some reliable, all-in-one solution that may automatically fix Core Web Vitals issues, Contact Us , We use bleeding-edge techniques to optimize LCP, INP, and CLS, giving your site an instant boost in speed and user rating – without any coding!