Google claims page speed affects ranking, but it doesn’t influence the SEO score over quality content. Yet, a slow speed does ruin the visitor’s experience. In fact, a delay of 3 to 4 seconds and the website conversion rate drops by 4.42% on average for each passing second.
The ideal speed for any website is 0 to 2 seconds. And you can only get this when you use speed testing tools and optimization techniques to reduce your load speed. However, these speed testing tools show different performance scores, which brings into question their accuracy.
In our GTmetrix vs. PageSpeed Insights review, we’ll look for that answer. Are the tools equally efficient? Is one better than the other? Do they complement each other? Let’s dig in.
What is GTmetrix?

GTmetrix is a freemium website performance tool running on Google Lighthouse. The aggregate score this tool would give you is likely to be more or less similar to that provided by any other tool running on the Lighthouse platform. However, the integration style is the differentiating factor.
You can tweak the testing location, web browser, screen resolution, and connection speed. As a consequence, the score that you can derive from this tool can often be significantly different from the one shown by PageSpeed Insights.
Fun fact: GTmetrix used the PageSpeed and YSlow libraries when it first launched. They switched to Lighthouse at the end of 2020.
What is PageSpeed Insights?

PageSpeed Insights is Google’s own solution for webmasters to improve their site speed. It is a free tool that doesn’t allow modification of any kind on the user end.
With PageSpeed Insights, you get reports that highlight your webpage speed on both desktop and mobile. If we’re going by plain logic, PageSpeed Insights should be your main tool for testing speed. After all, it is Google’s search engine you want to rank on.
However, even for PageSpeed Insights, Lighthouse is still a key determiner of the metric scores.
Since the majority of the tools rely on Lighthouse, it’s more about which tool you feel comfortable with. You will get the basic lab data from Lighthouse for all of these tools anyway.
GTmetrix vs PageSpeed Insights: Features Comparison
Both tools share the open-source Lighthouse libraries, which means they have a startling number of similar features. Yet, a website scoring 79% on GTmetrix can easily get something like 93 points on PageSpeed. Let’s see where they differ.
Performance Scoring
Both GTmetrix and PageSpeed Insights have first contentful paint (FCP), total blocking time (TBT), speed index, largest contentful paint (LCP), time to interactive (TTI), and cumulative layout shift (CLS) as metrics. These are the core web vitals, and getting these in the green zone improves your page speed significantly.
The GTmetrix grade is a weighted average of the performance and structure score. The performance score has a 70% stake in the outcome versus the 30% contributed by the structure score. What does this mean?
The GTmetrix performance score is the authentic page speed. The structure score represents a visitor’s experience while navigating the website.
Together, the two metrics form the total GTmetrix score. This score comes from the website’s performance in the past and present as Lighthouse tracks the data and continues to update it over time.
The PageSpeed Insights score reflects how your website performs in the real world against other websites. It uses both field data and lab data. Here’s what those two mean.
The field data compiles the reports from the last 30 days in the Chrome User Experience Report. In other words, how does the user experience on your website hold up in comparison to other web pages?
The lab data is the fixed set of conditions – these are the FCP and FCI. You have to shift the numbers to the green zone.
Essentially, GTmetrix and PageSpeed Insights both use past performance data. However, their source of data is different. The data on GTmetrix is from Lighthouse monitoring, while the data on PageSpeed Insights is from anonymous user reports on various sections of the web. This is part of the reason why scores can often increase and fluctuate several times within the day.
In both cases, you should focus on the six Lighthouse metrics to get a high score.
Monitor and Alerts
PageSpeed Insights is a real-time tool. You have to manually enter the URL every time you want to get a speed report.
However, you can set up GTmetrix to track page speed daily, weekly, or monthly. All you have to do is set the parameters; if the site underperforms, you will receive alerts on the issue. If your site suddenly goes offline, you will know.
The best part is the visual graphs accompanying these reports. You can find the exact time of data collection on the graphs. There are indicators for you to find key changes.
In summary, PageSpeed Insight only provides manual reports. GTmatrix generates automatic ones.
Test Location
The distance between the server and the test location plays a key role in the loading time of a website.
Suppose that the server of a site is in Vancouver. So the further your test location is from Vancouver, it will take longer for the server to receive the request. Conversely, the closer your test location is to Vancouver, the server request will be received more quickly, and the site will load faster.
You can change the test location to get a more accurate report from GTmetrix. PageSpeed Insights doesn’t allow you to change the location, but we assume it calculates the test location internally anyway.
Device and Browser

If you register on GTmetrix, you can get reports on the website’s loading time from different devices and browsers. You can try out interesting combinations and get a lot of specific and granular data. For instance, you can check the loading speed of your site or web pages on the Mozilla browser when used on a specific model Samsung or Apple device. However, this is something you only get if you register.
PageSpeed only analyzes the overall speed on desktop and mobile. You can’t go deeper with your specifications.
Suggestion and Solutions
Both tools explain the performance score through red, orange, and green. The shades determine how poorly a metric is performing.
Under each metric report, you can find the reason for the low score on GTmetrix. Additionally, they have links to blogs on how to improve the issue. However, you have to resolve the problem on your own based on the resources available online.
PageSpeed Insights directs you on how to optimize the website. It suggests plugins and extensions which can take care of the issue too.
Waterfall Chart

A waterfall chart is the visual depiction of the loading speed of each resource, appearing request-by-request. These are the HTML, CSS, and JS of your website.
The resources descend sequentially. Meaning the first resource on the chart is the quickest to load. This is a free feature from GTmetrix. If you log in, you can get access to how the page uses each resource, providing further insight.
On the other hand, PageSpeed Insights chose to skip this feature altogether. In its defense, we can say that this is not something most people would understand anyway – you need high technical knowledge to read and use the waterfall chart – so this may not necessarily be a significant exclusion.
GTmetrix vs PageSpeed Insights: Pros and Cons
In the GTmetrix vs. PageSpeed Insights list of pros and cons, both tools seem to hold up equally. GTmetrix, especially, has been through some fixes over the years and has really leveled up.
Pros of GTmetrix
- GTmetrix can create a video of your page loading from the user’s perspective. This way, you know exactly how the page loading is taking place.
- It can analyze the page speed depending on whether an AdBlock is on or off for a browser.
- Offers metrics such as Onload Time and Time to first byte (TTFB). TTFB measures how long it takes for a browser to receive the first set of data from a web server.
Pros of PageSpeed Insights
- The field data is the same data used for Core Web Vitals. PageSpeed Insights works with field data, which means this is the deepest glimpse you get into how Google views your website.
- You can see the speed on a mobile device if it’s working on a slow 4G connection.
- The “opportunities” section has actionable tips. You have direct links to extensions and plugins that can solve your issues.
- It measures website speed against the slowest connection. You can prepare for the worst-case scenario for these users.
Cons of GTmetrix
- The default settings report for the best-case scenario. Your score is based on a fast internet speed, desktop user, and Chrome browser from a Vancouver server. In reality, you should always be speed-testing for the worst situations.
- You can only analyze 3 URLs for free. If you want to customize and get deeper reports, you have to sign up and pay.
Cons of PageSpeed Insights
- PageSpeed Insights ignores a couple of important metrics. A TTFB report only shows up if your score is atrocious. If it’s in the middle ground, you won’t know.
- PageSpeed Insights is too harsh with lab data. Sometimes, a website’s loading time is excellent, but the lab data leads to disappointing results.
GTmetrix vs PageSpeed Insights: Expenses
PageSpeed Insights is a completely free tool provided by Google for your benefit. And since it’s a free tool, you should not be too surprised by the fact that it lacks some of the advanced features we found in GTmetrix.
When it comes to GTmetrix, however, it is also free but only for up to three URLs. You can access more websites and change the default speed testing settings once you sign up.
They don’t offer a free trial. If you want to pay for the premium version, you will have to dish out $14.95 per month. This is cheap if we compare it to other freemium tools, but it’s not the most affordable option by any means.
If you own a relatively small business and pricing is a major issue for you, then you should opt for PageSpeed Insights. It should be more than sufficient for your needs.
GTmetrix vs PageSpeed Insights: What Customers Think
To conclude our GTmetrix vs. PageSpeed Insights comparison, we took a look at the consensus on product review websites.
G2
GTmetrix has a score of 4.5 on G2, which makes it obvious how much users like the tool. Its score is derived from the average scores of 37 reviewers.
The general sentiment is that GTmetrix is the better of the two (PageSpeed Insights). The only drawback is the slight delay between reports if you use up your three free URLs daily.
Unfortunately, G2 hasn’t listed PageSpeed Insights at all for review.
Software Advice
GTmetrix flaunts a score of 4.87 out of 5 from 31 reviewers. Customers find the detailed report more impressive than anything else. The automated testing function is another bonus.
The main issue for reviewers appears to be limited server locations and a slightly confusing user interface. There are lots of tutorials, though, some from GTmetrix themselves, to make up for it.
Another issue appears to be how GTmetrix changes the metrics occasionally without notifying customers.
Unfortunately, Software Advice hasn’t listed PageSpeed Insights at all for review.
TrustRadius
Google PageSpeed Insights has a solid score of 9.4 out of 10 on TrustRadius. This is from 22 reviewers.
GTmetrix loses at a mere 9.2. However, we must note that it’s the average derived from only 12 reviews.
Overall, customers find the usability of PageSpeed Insights more favorable. There are more suggestions and simpler directions on what to do to improve. However, some customers do find the suggestions to be a bit too technical.
More customers are partial towards GTmetrix when it comes to customer support. Some have reportedly noticed an increase in visitors after using this tool, which translates to the fact that this tool can offer great ROI.
Final Thoughts
GTmetrix and PageSpeed Insights are both tools that have features other similar tools in the market lack. For this reason, both of these tools can work very well together, and our recommendation to you would be to do just that. Since one is a paid tool and the other one is free, you can use two for the price of one and take advantage of the strengths of each tool.
For instance, GTmetrix can serve an e-commerce business with multiple web pages better. The automatic reports can help you minimize site usage issues.
While on the other hand, new website owners who don’t understand the technicalities can benefit from PageSpeed Insights.
FAQ
1. What Is the Difference Between Page Speed Insights and Lighthouseu003cstrongu003e?u003c/strongu003e
Lighthouse is an extension, while PageSpeed Insights is a developer tool. PageSpeed Insights uses data from the Chrome User Experience report and lab data from Lighthouse.
2. Does Page Speed Insights Affect Seo?
PageSpeed Insights does not affect SEO in the sense that Google’s crawlers do not gather reports from the tool. But you can use PageSpeed Insights reports to understand how Google views your page.
3. What Is the Speed Index in GTmetrix?
The speed index is a metric that lets you know how fast your page visually loads above the fold. This means how much and how fast the site is visible to a user without scrolling down.