Free Online Tool

Website Speed Test

Run a free Google Lighthouse audit on any public URL. Measure Largest Contentful Paint, Cumulative Layout Shift, Total Blocking Time, and overall performance score.

What this tool measures

Powered by the official Google PageSpeed Insights API, this tool runs a real Lighthouse audit against any public website. The same engine Google uses to rank pages.

Performance score (0-100): overall page speed grade combining all metrics.
LCP (Largest Contentful Paint): time to render the largest element. Good: under 2.5s.
CLS (Cumulative Layout Shift): how much the page jumps around as it loads. Good: under 0.1.
TBT (Total Blocking Time): time the main thread was blocked by scripts. Good: under 200ms.
FCP (First Contentful Paint): time to first text or image. Good: under 1.8s.
Speed Index: how quickly content visually populates. Good: under 3.4s.

We also report scores for Accessibility, Best Practices, and SEO — all four scores are visible side-by-side.

How to use

Enter a public URL such as https://example.com.
Choose Mobile (Google's default for ranking) or Desktop.
Click Run Speed Test and wait 30-60 seconds for the first scan.
Review the four scores and Core Web Vitals breakdown.
Use the issues list to prioritize fixes.

FAQ

Why does the test take 30-60 seconds?

Google Lighthouse runs a real headless browser, loads your page, simulates a slow 4G mobile connection, and measures every frame. Running locally would take the same time; the difference is we let Google's servers do the work.

Why is my Performance score lower on Mobile than Desktop?

Mobile audits simulate a slow 4G connection and a less powerful CPU. Most websites score 10-30 points lower on mobile. Google uses mobile scores for ranking on most queries, so optimize mobile first.

What is a "good" Performance score?

90+ is fast, 50-89 is needs improvement, below 50 is slow. Aim for 90+ on desktop and 70+ on mobile for SEO-sensitive pages.

How is this different from the Security Scorecard?

Security Scorecard checks SSL, headers, and HTTPS configuration. Speed Test measures actual page load performance. Run both for a complete picture: secure + fast.

Is the data accurate?

Yes. This is the same Lighthouse engine and same PageSpeed Insights API that Google uses. Results match what you would see on web.dev/measure or pagespeed.web.dev.

Are there rate limits?

Google PageSpeed Insights has a generous free tier (25,000 requests per day across all unauthenticated users globally). For typical use you will not hit this. If you need batch scans, get a free API key from Google Cloud Console.