How Some Developers Fake a 100 Score on Shopify Google PageSpeed
Every day we review dozens of websites and provide free recommendations for improving loading speed. Because of that, we regularly see all kinds of optimization approaches — some legitimate, and some questionable.
At first glance, the Shopify store we recently analyzed looked great. Everything seemed clean and professionally built.
However, when we ran a performance test using Google PageSpeed Insights, the results were not perfect but still quite high:
96/100 on mobile
98/100 on desktop
At first, this might seem like an excellent result. But when we started analyzing the technical setup of the Shopify store more carefully, we noticed several things that raised questions about how these scores were achieved.
In this article, we’ll explain:
• How some developers artificially increase Shopify PageSpeed scores
• Why a 100 score on Shopify doesn’t always mean the site is fast
• What real Shopify speed optimization actually looks like
Understanding the difference between real performance optimization and manipulated PageSpeed scores can help store owners avoid costly mistakes when hiring developers or SEO specialists.
Webpagetest's measurement is broken. GTmetrix shows over 20 seconds, but the resource loading graphs show a time of around 8 seconds.
Webpagetest measurement with an error
GTmetrix Test
If we take into account that the GTmetrix score also includes a 17-second delay caused by an external tracking script, the result still looks acceptable.
In situations like this, optimization reports usually say that the website is almost perfect, and that only a few minor improvements remain — such as enabling server push, adjusting resource loading, or optimizing several scripts.
At first glance, everything appears normal.
But the real question is:
What is actually happening behind the scenes of this “perfect PageSpeed score”?
Hello — I Am the PageSpeed Bot
Let’s take a closer look at what happens when Google PageSpeed Insights (Lighthouse) scans a website.
When the Lighthouse bot opens a page, it does not necessarily see the exact same version of the website that real users see in their browsers.
Some developers intentionally configure their sites so that PageSpeed receives a simplified or optimized version of the page, while regular visitors load the full version.
This can artificially increase performance scores.
What Lighthouse May See
When the PageSpeed bot loads the site, it may receive a minimal HTML structure like this:
<head>
<title>arsagro</title>
<style>
body {
background: url(/image/templates/mob.jpg);
background-size: cover;
}
</style>
<link href="catalog/view/theme/revolution/stylesheet/stylesheet_min.css" rel="stylesheet">
<style>
#top2 .search {margin-top: 22px;}
#top2 #logo {margin-top: 8px;}
</style>
<link href="/catalog/view/theme/default/stylesheet/blog/module.min.css" type="text/css" rel="stylesheet" media="screen" />
<script src="/catalog/view/javascript/jquery/jquery-2.1.1.min.js"></script>
<script src="/catalog/view/javascript/jquery/owl-carousel/owl.carousel.min.js"></script>
<script src="/catalog/view/javascript/revolution/javascript_min.js"></script>
</head>
<body>
</body>
</html>
This version of the page loads almost instantly, because it contains only a small amount of code.
As a result, PageSpeed may report very high performance metrics.
What Happens Behind the Scenes
In some cases, websites detect when the visitor is a PageSpeed or Lighthouse bot.
If the request contains a Lighthouse user agent, the server can respond with a different version of the page that is specifically optimized for testing tools.
Example logic used on some websites:
This technique makes it appear as though the website loads extremely fast in performance tests.
However, real users may still experience slower loading times, because they receive the full version of the site with all scripts, apps, and tracking tools enabled.
Why This Matters for Shopify Stores
For Shopify stores, performance optimization should focus on real user experience, not just test scores.
A high Shopify PageSpeed score does not automatically mean your store is optimized correctly.
Real Shopify optimization involves:
• reducing unnecessary apps
• optimizing images and media
• improving theme code structure
• minimizing JavaScript execution
• optimizing third-party scripts
These improvements affect actual store performance, not just Lighthouse metrics.
Key Takeaway
If you see a Shopify store with a perfect 100 PageSpeed score, it does not always mean the site is truly optimized.
Sometimes it simply means the testing tool is receiving a different version of the page than real visitors.
When evaluating Shopify performance, always look beyond the score and focus on real loading behavior and user experience.
