Google's free tool for measuring page performance and Core Web Vitals in the lab and the field.
Official siteGoogle PageSpeed Insights (PSI) is a free tool that analyses a URL and reports how fast it loads and how it performs, on both mobile and desktop. It combines two data types: lab data from a single Lighthouse run, and field data — real Chrome user measurements from the Chrome UX Report (CrUX) — for the site's actual Core Web Vitals.
The field data is what matters for SEO, because Core Web Vitals (LCP, INP and CLS) are a Google ranking signal, and PSI shows whether real users pass them. The catch: CrUX field data only appears for pages with enough Chrome traffic, and the lab score is a single snapshot that can vary run to run, so it is a guide, not a guarantee.
PSI runs Lighthouse and surfaces CrUX field data to score performance and diagnose what to fix.
PSI is the performance-diagnosis layer for technical SEO. It overlaps with the Core Web Vitals report in Search Console, but PSI works on any single URL and adds Lighthouse-level detail on how to fix it. In dev workflows the Lighthouse engine underneath PSI runs locally and in CI.
Strength: free, authoritative on Core Web Vitals (it uses the same CrUX data Google ranks on), and specific about fixes. Limit: lab scores fluctuate between runs and can mislead if over-weighted; field data is missing on low-traffic pages; and the score is not a direct ranking multiplier — passing Core Web Vitals is the goal, not chasing a perfect 100.
We use PSI field data to confirm whether real users pass Core Web Vitals, then work the lab diagnostics into our technical-SEO and web-dev backlogs. We validate against the Search Console Core Web Vitals report and CrUX rather than fixating on a single Lighthouse score.
Google's free reporting on how your site performs in Google Search and how Google crawls and indexes it.
A desktop crawler that scrapes a website like a search engine to expose technical SEO issues.
A global CDN, DNS and security platform that sits in front of websites to speed and protect them.
Common questions
Straight answers on how this fits your marketing and build.
Lab data comes from a single controlled Lighthouse test. Field data comes from real Chrome users via the Chrome UX Report and reflects your actual Core Web Vitals — which is what affects rankings.
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