What Are the Common Issues Flagged by PageSpeed Insights That Typically Have the Most Substantial Negative Impact on SEO, and How Can They Be Addressed?


Common issues flagged by PageSpeed Insights that negatively impact SEO include slow server response times, unoptimized images, render-blocking resources, unused JavaScript, excessive DOM size, and inefficient caching strategies. Addressing these issues involves a combination of server optimization, asset optimization, and efficient resource loading practices.

Slow Server Response Times

Slow server response times can significantly impact web performance and SEO. Optimizing server response times can improve overall page load speed and user experience.

Implement a Content Delivery Network (CDN)

A CDN can distribute your content across multiple servers globally, reducing latency and loading times for users [Why Performance Matters, 2023].

Server Caching

Implement server-side caching to deliver pre-rendered pages or components quickly [Time to First Byte (TTFB), 2020].

Optimize Database Queries

Minimize latency by optimizing database queries and using indexing [Optimize CSS Delivery, 2022].

Unoptimized Images

Large, unoptimized images can slow down page load times significantly.

Use Efficient Image Formats

Utilize modern image formats like WebP for better compression and quality [Use WebP Images, 2023].

Responsive Images

Implement responsive images using the <srcset> and <sizes> attributes to serve appropriately sized images for different devices [Serve Responsive Images, 2023].

Enable Lazy Loading

Delay the loading of non-essential images using lazy loading techniques [Lazy Loading, 2023].

Render-Blocking Resources

Render-blocking resources delay the time it takes for a page to be visibly rendered by a browser.

Optimize CSS Delivery

Minify CSS files and use <link rel="preload> for critical CSS to improve render times [Optimize CSS Delivery, 2022].

Defer or Async JavaScript

Load non-critical JavaScript files asynchronously or defer their loading to avoid blocking the main thread [Defer Non-Critical JavaScript, 2023].

Critical Rendering Path Optimization

Inline essential styles and scripts to minimize the critical rendering path and prioritize above-the-fold content [Understanding the Critical Rendering Path, 2023].

Unused JavaScript

Excessive JavaScript that is not used on the initial page load can slow down performance.

Code Splitting

Utilize code splitting techniques to load only the necessary JavaScript files [Code Splitting, 2023].

Tree Shaking

Remove unused JavaScript code through tree shaking techniques [Optimize Lightning Web Components, 2021].

Excessive DOM Size

Large DOM sizes can increase memory usage and negatively impact rendering performance.

Minimize DOM Depth

Flatten the DOM tree to reduce complexity [Minimize DOM Size, 2023].

Avoid Excessive Nodes

Limit the number of DOM nodes wherever possible [Rendering Performance, 2022].

Inefficient Caching Strategies

Poor caching strategies can lead to repeated downloads of resources, increasing load times.

Implement Browser Caching

Use HTTP caching headers to store resource copies in the user’s browser [HTTP Caching, 2023].

Service Workers

Leverage service workers to cache assets and enable offline functionality [Service Worker Caching, 2023].


Addressing common issues flagged by PageSpeed Insights involves a multi-faceted approach that includes server optimization, asset optimization, and efficient resource loading practices. By focusing on these areas, you can improve page load speeds, enhance user experience, and positively impact SEO.