Mobile Page Speed Analyzer
Analyze and optimize mobile page speed
PageSpeed Insights costs nothing. In practice a key is still required: keyless requests run against a shared Google project with a daily limit of 0 and return HTTP 429. If the site owner has set GOOGLE_PAGESPEED_API_KEY this works out of the box; otherwise paste your own free key.
No mobile test run yet
A typical mobile Core Web Vitals budget is LCP under 2.5s, INP under 200ms and CLS under 0.1.