If you want your website to rank higher in Google search results, simply producing quality content isn't enough. Page experience is also a crucial ranking criterion for search engines. Therefore, Google has developed Core Web Vitals metrics to measure user experience.
In this guide, we will examine in detail what Core Web Vitals are, why they are important, and how you can improve your LCP, INP (which replaced the old metric FID), and CLS scores.

What are Core Web Vitals?
Core Web Vitals are performance metrics that measure the actual user experience of a web page. Google uses this data to evaluate how quickly a page loads, how quickly it responds to user interactions, and how stable the visual layout remains during loading.
The main metrics are:
LCP (Largest Contentful Paint) – The loading time of the largest visible content on the page.
INP (Interaction to Next Paint) – How quickly the site responds to user interactions.
CLS (Cumulative Layout Shift) – Unexpected layout shifts that occur while the page is loading.
Note: FID (First Input Delay) has been removed from Core Web Vitals as of March 2024 and replaced by INP (Interaction to Next Paint). You may see FID mentioned in older sources, but it is recommended to focus on INP in new optimizations.

Ideal Core Web Vitals Values
Google's recommended target values:

1. How to Improve LCP (Largest Contentful Paint)?
LCP measures how long it takes for the largest content element (usually a large image or header area) that a visitor sees to load.
To improve LCP:
Choose fast hosting using NVMe SSD.
Enable HTTP/2 or HTTP/3 support.
Reduce server response time (TTFB).
Use a CDN to deliver content from the closest point to the visitor.

Compress hero images and use modern formats (WebP or AVIF).
Prioritize loading critical CSS.
Remove unnecessary JavaScript files.
Enable page caching.

2. How to Improve INP (Interaction to Next Paint)?
INP measures how quickly your site responds to user interactions such as clicking a button, filling out a form, or opening a menu.
Improvement suggestions:
Break down long JavaScript processes into smaller chunks.
Remove unused JavaScript code.
Reduce heavy third-party scripts.
Avoid unnecessary animations.
Don't burden the main thread with unnecessary processes.
Avoid large DOM structures.
Move intensive processes to web workers whenever possible.

3. How to Reduce CLS (Cumulative Layout Shift)?
CLS measures the unexpected shifting of content as a page loads. This negatively impacts user experience and can lead to accidental clicks.
To reduce CLS (Clear Page Load Time):
Define width and height values ​​for images.
Set fixed sizes for ad spaces.
Load fonts correctly and use `font-display:swap`.
Reserve space in advance for dynamic content.
Avoid adding new content to the top section before loading is complete.

4. Optimize Images
Images often constitute the largest load on a page.
For better performance:
Prefer WebP or AVIF formats.
Compress images before loading.
Use `srcset` for responsive images.
Load images at the bottom of the page with Lazy Loading.
Avoid using images with excessively large resolutions.

5. Minify JavaScript and CSS Files
Each additional file can increase page load time. Optimizations that can be done:
Apply the Minify operation.
Combine CSS and JavaScript files (if applicable).
Clean up unused CSS rules.
Remove unnecessary libraries.
Load non-critical JavaScript files using defer or async.

6. Create a Strong Caching Strategy
Caching reduces server load while providing faster responses to visitors.
Recommendations:
Page caching
Browser caching
Object Cache (Redis or Memcached)
Opcode Cache (OPcache)
CDN caching

7. Improve Server Performance
A slow server can negatively impact even the best optimized website.
Things to consider:
Use the latest PHP version.
Regularly optimize the database.
Remove unnecessary plugins.
Ensure LiteSpeed, Nginx, or Apache are correctly configured.
Choose a hosting plan with sufficient CPU and RAM resources.

8. Review Third-Party Services
External services can significantly impact performance. Specifically:
Advertising networks
Live chat tools
Heat map applications
Analytics services
Social media widgets
Use only the services you truly need and delay their installation if possible.

How to Measure Core Web Vitals? It's important to regularly analyze your performance. You can use:

Tools:
Google PageSpeed ​​Insights
Google Search Console (Core Web Vitals report)
Lighthouse
Chrome DevTools
Chrome User Experience Report (CrUX)
These tools help you analyze both lab data and real user data.

Most Common Mistakes
Common issues that lower Core Web Vitals scores:
Large, unoptimized images
Excessive number of WordPress plugins
Heavy theme usage
Unused CSS and JavaScript files
Shared and low-performance hosting
Numerous third-party scripts
Lack of caching
Failure to regularly optimize the database

Conclusion
Core Web Vitals is not just a technical performance metric; it is also a crucial criterion that directly impacts user experience and SEO success. Pages that load quickly, respond promptly to interactions, and are visually stable both keep visitors on the site longer and positively affect your visibility in search engines. By regularly monitoring LCP, INP, and CLS metrics; You can sustainably improve your website's performance through actions like image optimization, caching, server optimization, and the removal of unnecessary resources. Regular performance analysis and the identification of new optimization opportunities are crucial investments in long-term SEO success.