Website Speed Test

What the Website Speed Test checks

This speed test loads your page in Google’s Lighthouse through PageSpeed Insights on a simulated mid-range phone and a throttled mobile connection, the conditions where slow pages hurt most. You get the performance score from 0 to 100 and the timings behind it: First Contentful Paint (when something first appears), Largest Contentful Paint (when the main content appears), Speed Index, Total Blocking Time and layout shift, plus how long the server took to answer.

Next to the timings, the test shows what the page is made of: total page weight, the number of requests by type and by host, the element that becomes the Largest Contentful Paint, and whether text is compressed and served over HTTP/2 or HTTP/3. When Chrome has enough real-user data for the page or site, its field results are shown too. A run usually takes 20 to 40 seconds.

Why it matters

Visitors leave slow pages, particularly on phones, and every extra second before the main content appears costs attention and sales. Speed also feeds into Google Search through the Core Web Vitals of real visitors.

A single score hides the cause. Most slow pages are slow for a few concrete reasons: oversized images, render-blocking CSS and JavaScript, too many third-party scripts or a slow server. The test lists the ones that apply to your page, so you know where an hour of work pays off.

How to fix common problems

Start with the largest items: compress and resize images, serve them as WebP or AVIF, and give the main image fetchpriority="high" instead of lazy-loading it. Our guide to page weight shows where the bytes usually go.

Remove or defer what blocks rendering: inline the critical CSS, load scripts with defer, and drop third-party tags you no longer use. See render-blocking resources and third-party code.

Speed up delivery: turn on Brotli or gzip compression, HTTP/2 or HTTP/3, long cache lifetimes for versioned files and a CDN close to your visitors. Then run the test again; the full PerfoMetrix audit adds security, SEO and AI readiness to the same report.

Questions

Why does my score change every time I test?

Lab tests vary with server load, network conditions and third-party scripts that load differently each time. Swings of a few points are normal; compare the underlying timings and look at trends over several runs.

Is this the same as Google PageSpeed Insights?

It uses the same engine: Google Lighthouse run through the PageSpeed Insights API on the mobile profile. We add page weight, request counts and delivery checks, and explain each finding with a fix.

Why is my site fast on my computer but slow here?

The test simulates a mid-range phone on a slower mobile connection, with an empty cache. Your own computer is faster, often close to the server and already has many files cached.

What is a good page load time?

Aim for the main content to appear within 2.5 seconds (Largest Contentful Paint) for most real visitors, and for a Lighthouse performance score of 90 or more on mobile.