Free Website Speed Test

What Is the Website Speed Test?

Speed is a ranking input and a conversion fact: visitors leave slow pages, and Google measures both the laboratory version of your page (a controlled test) and the field version (real Chrome users, shown in Search Console). This tool shows you both measurable views: a direct timing-and-weight measurement taken by our server just now, and — when Google’s free quota allows — the Lighthouse lab scores from Google’s own infrastructure. The field view exists only in your own Search Console.

The four scores answer different questions. Performance is the speed grade and the one tied to Core Web Vitals. Accessibility checks whether the page works for everyone. Best Practices catches outdated or risky techniques. The SEO category verifies the crawlable basics. Run mobile first: it is the stricter test and the one most of your visitors experience. For the on-page side of the same page, pair this with the SEO Audit Tool.

How to Use It

1. Paste the full URL of the page to test.
2. Choose Mobile (default — the stricter, more representative test) or Desktop.
3. Click Run Speed Test and wait — Lighthouse takes up to a minute.
4. Read Performance first, then the metrics table to see which number is costing you.

What You Get

Lab data vs field data — and why they disagree

This test runs on lab data: a controlled experiment where the page is loaded under simulated conditions — a set device, a throttled connection, a cold cache — the same way every time. That repeatability is what makes lab data useful for diagnosis, because when a score changes you know the page changed, not the weather. The scores and metrics shown here come from Google's own Lighthouse testing through the PageSpeed Insights API, so the numbers you see are Google's measurements, not ours.

Field data is the opposite: real measurements from real visitors, gathered over a rolling 28-day window, reflecting their devices, networks, and locations. The two routinely disagree — a page can score well in the lab yet struggle in the field if most visitors use modest phones on slow networks, or the reverse once caching helps returning users. The disagreement is not an error in either source. When the two conflict, remember that Google's ranking assessments use field data, because that is the experience visitors actually had.

Reading the metrics — which number to fix first

For a typical page, start with Largest Contentful Paint and Cumulative Layout Shift, because they describe the two moments visitors judge most harshly: how long until the main content appears, and whether the page jumps around while it loads. Total Blocking Time comes next — it measures how long the main thread was too busy to respond, making it the lab stand-in for sluggish taps and clicks. First Contentful Paint and Speed Index fill in the early picture: when anything first renders, and how quickly the visible page fills in.

Work on the worst red number first rather than polishing what is already green — one fix aimed at the biggest delay usually outweighs five cosmetic tweaks. A slow LCP most often traces back to a heavy hero image, slow server response, or render-blocking files; a poor CLS usually comes from images and embeds without reserved space, or content injected above what is already on screen. Change one thing, rerun the test, and confirm the metric actually moved before moving on to the next.

Privacy: your entry is sent to Google’s public API services to return live results, under Google’s terms. Nothing is stored on our servers.