Google Page Speed Index & PageSpeed Insights | Quattr Inc

Google Page Speed Index & Page Speed Insights

How a Page’s Load Speed and Speed Index Score Impact Your Website’s Visibility

By Colton Miller

In 2026, fast page load time is more important than ever. Users expect websites to load instantly, and even small delays can make them leave. While Speed Index is not a Core Web Vital, it still plays a key role in understanding how quickly users see your content.

Google continues to prioritize user experience, and how fast your page looks and feels during loading can impact engagement and performance. Speed Index measures how quickly the visible parts of your page appear, helping you improve those first few seconds that matter most. In this guide, you’ll learn what Speed Index is, how it works, and how to improve it for a smoother and faster user experience.

What You Need to Know

PageSpeed Insights (PSI) is a free Google tool that analyzes your website’s performance on mobile and desktop.

It gives you a performance score (0–100) based on real user data and lab data.

Speed Index is one of the metrics inside PSI that shows how fast your page content becomes visible.

PSI also tracks Core Web Vitals like LCP, INP, and CLS, which impact SEO.

Use PSI to find issues and get suggestions to improve speed, user experience, and rankings.

What is Google Page Speed Index?

Speed Index is a score that measures how quickly the content of a web page is displayed visually. Speed Index represents the average time it takes for your page content to become visually complete, focusing on what users actually see during the loading process rather than just when the page technically finishes loading.

What Is Google Speed Index Score?

Speed Index is a score that measures the average time it takes for a web page to become visually complete. Introduced in 2012, Speed Index metric has become critical for evaluating website performance. Since 2021, Google's Page Experience update has made Core Web Vitals (which include loading performance) a confirmed ranking factor for all searches, with mobile-first indexing prioritizing mobile performance.

Why is Page Speed Important?

Google’s core goal for search is to help users accomplish actions as quickly and efficiently as possible. To achieve this, Google places significant importance on page loading times. A fast-loading website is critical for providing a seamless user experience and improving your website’s search engine rankings. One study found that your ROI can be impacted by as much as 20% for every second your site takes to load on mobile devices.

A high PageSpeed Insights score also means that your website is likely to perform better on various device types.

Speed Index and Core Web Vitals

While Speed Index provides valuable insights into visual loading performance, it's important to understand that Speed Index is NOT a Core Web Vital. Speed Index is a lab metric used for diagnostics, while Core Web Vitals are field metrics that directly impact Google rankings.

Core Web Vitals are essential metrics defined by Google to evaluate the user experience of a website. These metrics are critical for understanding and improving your site’s performance. The three main Core Web Vitals are:

1. Largest Contentful Paint (LCP)

2. Interaction to Next Paint (INP)

3. Cumulative Layout Shift (CLS)

How Are Google PageSpeed Insights And Speed Index Calculated?

The PageSpeed Insight tool by Google calculates the page loading time of your web pages.

Google PageSpeed Insights Scoring for Dummies

Google’s PageSpeed Insights tool gives you a score between 0-100, with 100 being the fastest loading time. A website with a PSI score of 90 or above is considered to be performing well. While a website with a PSI score of 0-30 is considered to be performing poorly. Anything in between is considered ‘Needing Improvement’ but, in reality, is deemed to be average if not above average.

While there are dozens of factors and a handful of metrics being calculated for PageSpeed Insight scoring, the PageSpeed Insights tool measures three primary aspects of your website that tend to impact a site’s loading time:

  1. The server response time is the time it takes for the server to send the first byte of information to the browser. The time to first meaningful paint is the time it takes for the content on the page to first appear.
  2. The download time is the time it takes for the full page to be downloaded.
  3. The total page size is the size of the page in bytes.

Google Speed Index Scoring for Dummies

As a general concept, Speed Indexing is the score of the average time it takes for your page and its content to be available and visible to a browser/user. Current Speed Index scoring incorporates HTTP Archive data to establish performance benchmarks. This allows PageSpeed Insights to compare your site's Speed Index against real-world web performance data, providing more meaningful context for your scores.

The result of this is a simplified scoring system for the Speed Index metric. With each color-coded score, there is an associated value. This is compared with and shown in seconds. The scoring rubric is the following:

  1. Green (fast): 0-3.4 Seconds
  2. Orange (moderate): 3.4-5.8 Seconds
  3. Red (slow): Over 5.8 Seconds

Note: These thresholds may be updated as web performance standards evolve. Always refer to current PageSpeed Insights for the most recent benchmarks.

What brings down your Google Page Speed Index Scores?

There are a few things that can bring your page speed scores down. One of the biggest culprits is unoptimized and oversized images. If your website has a lot of images, it can take longer to load if they are inappropriately sized for the page and unoptimized for a user's network.

Another thing that can affect your page speed score is the number of HTTP requests your website makes. HTTP requests are the requests your browser makes to load all the elements on a page. The more requests your website makes, the longer it will take to load.

One other common trend for a poor page speed score is under-serving your website or more technically bandwidth-throttling your site from its housed server to the end-user. This often occurs with cheap or shared hosting options from hosting companies and registrars. While this usually affects smaller sites and businesses, it can affect larger sites especially if the site usage and access are not increased as the site and its popularity expand.

How To Improve PageSpeed Insights Scores?

There are many ways you can improve the page loading speed of your website to increase its Page Speed Index. Almost anything you do to optimize your site and its pages tends to lead to better PageSpeed Insight scoring. Below we will share some of the best ways to improve your Speed Index scores.

The first thing to examine is the server and network utilization. Images are another thing to evaluate within this utilization. Here are some tips you can use to improve and optimize images:

  1. Compress images using tools like TinyPNG or ImageOptim.
  2. Resize images to appropriate dimensions for their display context.
  3. Implement lazy loading to defer off-screen image loading.
  4. Use modern image formats like WebP when possible.

For optimizing PageSpeed, you only need to understand one simple question:

“Is there enough bandwidth available?”

If not, then you should consider creating a content delivery network (CDN), which will help optimize site files and offload some of the traffic from the server. Furthermore, you can use your CDN to serve static resources like images, CSS files, and scripts from global servers instead of hosting them on your own local servers, which might be poorly distributed or too remote from other servers that may be closer to the user. This will help reduce latency in serving those resources which will increase the page speed index score.

You can also reduce the amount of traffic on your website by using browser caching. This means that users won't have to download all of the same content again and again when they revisit your website because it will be stored in their browser cache.

Reduce the size of HTML, JavaScript, CSS, and other types of files on your site. This will decrease the overall load time as well as the number of bytes transmitted over the network. Be sure to use only what is needed and not more than necessary. For example, use CSS sprites instead of multiple images for particular elements in your design so that each image isn't downloaded separately from different sources each time it loads on screen.

Finally, compress images using tools like TinyPNG or ImageOptim to compress your images. You should also resize them if they are too large. Lastly, you can also set images to load as the page is scrolled through. Commonly referred to as lazy-loading, it effectively delays content from being fetched by the browser until a trigger occurs. This trigger could be a user scrolling to an element, a time delay, and more. This will defer some data transferring and could also help save you bandwidth usage over time.

Improving Your Speed Index Metric Scoring

While similar to improving your overall PageSpeed Insight scores, your Speed Index scoring can often improve by almost any optimization or improvement made to a page. However, beyond general optimizations, there are 3 specific suggestions provided to optimize your site's Speed Index scores:

  1. Text Visibility During Webfont Load
  2. Reduce JavaScript Execution Time
  3. Minimizing Main Thread Work

Text Visibility During Webfont Load

Making sure your site and page content remain visible while the page and its design are being loaded can make a positive impact on your Speed Index scores. Ensuring this happens is of course easier said than done. But with some slight code or even theme file changes, it is completely doable for almost anyone.

Including the HTML code [font-display: swap] in your [@font-face] page style can help you avoid the default hiding of text while font styles are being loaded. Here is a quick example of how this can look inside of a page’s HTML coding.

Reduce JavaScript Execution Time

Dropping the time it takes to execute JavaScript can be done in a multitude of ways. Some basic recommendations that can help improve these processes:

  1. Implement Code Splitting
  2. Minify or Compress Code
  3. Cache Code with PRPL Patterning
  4. Remove Unused Code

Minimizing Main Thread Work

This last one is certainly not for the faint-of-heart or technically timid. It is however something that can make a massive impact on the way your site and its page load. As a general overview, your browser has a render process. This process is responsible for taking raw HTML code and effectively building the page. This building process includes the information, formatting, styling, functionality, and more.

All of this processing and rendering is done mostly by default with something called the ‘Main Thread’ acting like the step-by-step instructions to build the page. Effectively the Main Thread is what your site uses to tell the browser what to grab when a page is being requested from a server.

In a general sense optimizing Main Threading for Speed Index scoring means telling the browser to fetch the content, formatting, and styling before fetching everything else like functionality, images, javascript, etc. for the page.

At a high level here are the top things to review and optimize when minimizing Main Thread work:

  1. Script Execution Evaluation
  2. Styling and Layout Handling
  3. Page Rendering Priority
  4. Parsing HTML and CSS Coding
  5. Script Parsing and Compiling
  6. Checking a Page’s Memory Usage

Existing tools that can help with Page Speed Optimization

You can use the following tools to test the loading speed of your website. These tools will also help show what is either passing or missing their own inspections and scoring rubrics. Each one provides solutions that when made can help ensure your website loads quicker.

  1. Google PageSpeed Insights: Google's PageSpeed Insights tool is a great way to test the loading speed of your website and get suggestions on how to improve it.
  2. Lighthouse (Chrome DevTools): Google Lighthouse, built into Chrome DevTools, provides comprehensive performance analysis including Speed Index measurements.
  3. GTMetrix: GTMetrix is another tool that you can use to test the loading speed of your website.

Scale Your Google Page Speed Optimization Efforts With Quattr

Quattr was built from the ground up to highlight page speed issues across your website and give you ways you can improve your page load time. The platform ranks recommendations in a unique way based on potential traffic to be gained, helping to direct your page speed improvement efforts effectively.

Long-term Strategies for Page Speed Optimization

While tools like Quattr, PageSpeed Insights, YSlow, and GTMetrix are invaluable for diagnosing and addressing page speed issues, a holistic strategy that includes regular audits, content optimization, and server performance enhancement is crucial for sustained success.

Regular Speed & Performance Audits

Regular performance audits allow you to proactively identify and address issues before they significantly impact user experience.

Content Optimization

Continually optimizing your content is essential for maintaining a fast-loading website.

Server and Hosting Improvements

Investing in high-quality hosting solutions and utilizing Content Delivery Networks (CDNs) can significantly reduce latency and enhance load times for users around the globe.

Google Page Speed FAQs

What is Google Page Speed in SEO?

Google Page Speed in SEO measures how quickly a website's content can be rendered in a web browser.

Why is Google Page Speed Important?

Google Page Speed is a factor that is used in the ranking algorithms of search engines, so website owners need to optimize their sites for speed if they want them to rank well.

What is Speed Index?

Speed Index is a metric used to measure the average time it takes for a web page to become visually complete.

How to Reduce Speed Index?

Several ways help reduce the Speed Index include optimizing images, minifying codes, caching content, and leveraging browser caching. Additionally, it is vital to remove any unnecessary content, minimize redirects, and use a CDN.

About The Author

Colton Miller has 12 years of experience in selling, servicing, supporting, and strategizing SEO. He has dealt with thousands of sites across hundreds of verticals and has also helped create and define scaled solutions for hundreds of thousands of SMBs and enterprise clients alike.

About Quattr

Quattr is an AI-native Search Visibility Platform founded in Palo Alto, California, built for mid-market and enterprise brands competing in the age of generative search. Quattr helps brands win visibility across traditional search and AI-generated answer surfaces.