Page speed test

Run a page speed test for mobile and desktop with Google Lighthouse. Review Core Web Vitals when available, compare a competitor and choose a fix.

Free, no account. Ten technical checks per hour, shared across these tools.

We send this public URL to our API and Google. Do not include passwords or private tokens. Successful tests can be cached for an hour.

Compare one public page on the same device. A comparison uses two checks.

Test device

This free page speed test combines Google Lighthouse lab tests with Chrome UX Report visitor data. LCP measures main content, INP measures response to interaction and CLS measures layout movement. Field results show the 75th percentile and visit shares in each band. Missing data stays missing. Server fetch timings are separate.

How to use this checker

Choose a page and device
Use a public HTML page. Mobile and desktop are separate Google Lighthouse tests. Adding a competitor uses two of the ten technical checks allowed per hour. Each device needs its own run.
Read visitor data before the lab score
CrUX aggregates eligible Chrome visits over a rolling 28-day window. Page data describes this URL; origin data covers the whole website. A small site may have no field data. LCP, INP and CLS together determine the field assessment; FCP and TTFB add context.
Work through the largest savings
Lighthouse runs in a controlled environment and estimates savings. Its score and timings vary. Savings overlap and should not be added together. Review the affected files, make one change and test again under the same device settings.
Keep a dated result
Download the JSON report with sources and timestamps. Successful tests are cached for an hour. A failed refresh may show an older result, labelled stale, for up to 24 hours. A shared link prefills the test; it does not freeze a report.

Questions about this checker

When Google has enough eligible Chrome traffic, we show real LCP, INP and CLS from CrUX for the selected device. Lighthouse supplies separate lab measurements and a performance score. Lab Total Blocking Time helps diagnose responsiveness but does not measure real visitor INP.

Google can exhaust the shared keyless quota, time out or fail to load a page. We say which happened and show any cached data or our own HTTP reading as a fallback. That reading has no Lighthouse score and cannot measure rendering or real visitors.

CrUX needs sufficient eligible public traffic. Its dedicated APIs also need an optional server key configured by AIGROW. Without it we use any field data still returned by PSI; history is unavailable. Missing data does not mean the page passes or fails.

At the 75th percentile, good means LCP at most 2.5 seconds, INP at most 200 milliseconds and CLS at most 0.1. Poor means LCP above 4 seconds, INP above 500 milliseconds or CLS above 0.25. The middle band needs improvement. FCP uses 1.8 and 3 seconds; TTFB uses 0.8 and 1.8 seconds.

No. Speed helps visitors use a page, but rankings and AI citations depend on many other factors. Use the SEO and AI crawler checks to review discoverability alongside performance.

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Check your business in AI answers

After fixing slow pages, use the free visibility scan to see which answers mention your business and what to work on next.

Run the free AI visibility scan