GTmetrix Speed Test Tool – How to Use It?

GTmetrix  - How To Use Speed Test Tool

When running an online business website, website speed is essential to attract more customers and succeed in the business. You can check whether your website is well-performing or not by using the GTmetrix speed test tool. It will help you with different parameters to analyse your site speed, identify the problem within the website, and recover those problems in the site.

In this blog, we will give you a good and clear explanation of GTmetrix and how to use it. So, if you’re ready, then let’s get right into it.

What is GTmetrix?

It is one of the most widely used tools for analysing site performance. When you put a website to the test, it will give you a performance score and a report that shows the current state of the site as well as some suggestions on how to improve it.

GTmetrix speed test tool

This tool is entirely free to use. However, if you want more features, such as unlimited report filters and resource usage graphs, upgrade to GTmetrix Pro, starting at £17.45 /month with the starter plan.

GTMetrix analyses the speed and performance of websites on desktop and mobile using a wide range of page speed optimisation factors. The free version of this tool has limited functionality. However, businesses with numerous websites and digital marketing firms benefitting from faster analysis can use paid plans to unlock advanced features.

Another thing to note is how GTmetrix uses results from Google PageSpeed Insights to create the performance score and recommendations. You don’t need to run the test on another tool because the results cover a wide range of performance metrics to present the report comprehensively.

Main Factors of GTmetrix

The test results must be accurate and relevant. After all, a precise result will allow you to make an informed decision about what will help improve the speed of your site.

You should consider these factors to improve test accuracy.

The number of tests: The test will vary according to the user traffic at the time of testing, so it would be best to try two or three times to get the best result.

Test subjects: For a more thorough analysis, test multiple posts and pages. This will aid in determining which needs to be optimised.

Test Location: When your website is targeting a global audience, your site should have to go to multiple locations to conduct the speed test. However, it will change when you target the local audience because you can choose the nearest location to set the target.

How to Use the GTmetix Tool?

Now that you know about the basics of GTmetrix, let’s get to the main topic of how to use the GTmetrix tool to test your site speed.

The basic version of GTmetrix is free to use and the best way to get started with the tool.

While you can go straight to the main page and begin analysing your site, we recommend first registering for a free account. It will give you much more flexibility in configuring your tests, like changing the testing location.

The first step is to go to the in the web browser

You can ask for registration, and based on your need, you can choose the account types. Here we have used the essential free type GTmetrix tool. Now you can see the GTmetrix dashboard below.

gt metrix dashboard

After you’ve created your free account, you can do the following:

  • In the box, enter the URL of your website.
  • To expand the extra options, click the Analysis Options accordion button.

You should make at least two choices to get an accurate picture of your site’s load times:

Using the drop-down menu, choose the location closest to your target audience.


gt metrix location

In the connection drop-down menu, choose Broadband (Fast). This will use a connection speed that is roughly average for London, United Kingdom, as a whole; you can select a different connection speed if that better suits your needs.

Once you run your test, GTmetrix will show you a summary like this,

gt metrix url details

It will give you information about grades and web vitals,

Six pieces of information are divided into two boxes in the summary box.

GTmetrix Score

These do not directly assess your performance. Instead, they attempt to assist you in understanding how well your site has been optimised for performance.

Letter grade: It is an overall score for optimising your site.

Performance: Essentially, this is your Lighthouse performance score based on the same analysis as Google’s PageSpeed Insights tool.

Structure: It is a proprietary score created by combining Lighthouse with some of GTmetrix’s own audits. It’s meant to represent how well-optimized your page is.

Web Vitals

These display actual performance data, emphasising Google’s new Core Web Vitals initiative.

LCP:  The Largest Contentful Paint time of the page, which measures how long it takes for the main page content to load. Google recommends that your LCP time is under 2.5 seconds.

TBT: It is a proxy for the First Input Delay (FID) metric in Core Web Vitals (FID is only available in accurate user data, so GTmetrix cannot directly test it). Your TBT should ideally be less than 150 ms.

CLS: It is the Core Web Vitals metric for Cumulative Layout Shift. It calculates how much your content shifts or moves as it loads. Your CLS score should be less than 0.1.

Below those two options, the advanced analytics options will there, and it is divided into six, such are,

  • Summary
  • Performance
  • Structure
  • Waterfall
  • History
  • Video


The Summary tab does not concentrate on a single topic. Instead, it summarises the most important information from some of the other areas of analysis.

gt metrix summary

Speed Visualization (shown above) lets you see how your site looks visually as it passes various performance metrics. For example, the Largest Contentful Paint metric allows you to see precisely what your site looks like at the time.

The Top Issues tab lists a few of your site’s most essential optimisation opportunities. However, you can find all of this information in the Structure tab so you can ignore these details for the time being.


The Performance section gives you a lot more performance measures and timing details. If you’re disappointed that the summary box only shows the Largest Contentful Paint time, this page more than makes up for it.

In the Performance Metrics section, you can see the metrics which mentioned below:

  • First Contentful Paint
  • Speed Index
  • Largest Contentful Paint
  • Time to Interactive
  • Total Blocking Time
  • Cumulative Layout Shift

And then, if you go to the Browser Timings section, you’ll get another nine metrics:

  • Redirect Duration
  • Connection Duration
  • Backend Duration
  • Time to First Byte (TTFB)
  • First Paint
  • DOM Interactive Time
  • DOM Content Loaded Time
  • Onload Time
  • Fully Loaded Time

gt metrix performance


The Structure section shows the outcomes of all of the performance optimization checks GTmetrix has run. These are the factors that contributed to the Structure score shown in the summary box.

gt metrix structure

GTmetrix will also indicate the potential effect of that tactic so you know where to direct your efforts:

When you click the sidebar section next to any check, GTmetrix will provide more information about what it means and specifics about how your site performed for that check.


The GTmetrix waterfall is one of the most useful tools for identifying bottlenecks in the speed of your website. It provides information about each HTTP status request on your site, including where and how quickly it loads.

gt metrix waterfall

Without going into too much detail, each asset on your website is its own HTTP request. An asset could be anything from an image file to a CSS stylesheet or script.

If the test summary box indicates that your site has 26 requests, it must load 26 assets. It also means that the waterfall analysis will have 26 different entries.

Each asset on your website must be located, transferred, and displayed. Each bar in the waterfall depicts all of the steps required for each asset and how long they take.


The Videos tab now includes two enhancements that allow you to watch a screen recording of your site loading:

  • You can slow down the recording to 1/4 speed to better see any content shifts or flashes of error content.
  • You can skip ahead to major timing milestones like the Largest Contentful Paint.


The History tab displays the results of multiple tests on one page in an easy-to-read graph. It’s useful for tracking how long it takes for your pages to load.

Another useful tool is the ability to add notes. For example, if you changed hosts or cached plugins, you could make a note in GTmetrix to see how that affected your load times.

GTmetrix’s free plan allows you to view up to three months of data, while paid plans provide longer retention.

Final Thoughts

If you want a fast website, you’ll need a comprehensive tool that can test it under various conditions. GTmetrix enables you to do just that. Setting up automatic monitoring and testing from various locations will give you a comprehensive picture of your website’s performance. We hope this guide helped you to get to know about GTmetrix.