Google PageSpeed Insights API vs Chrome UX Report (CrUX) API
Free API comparison
| Google PageSpeed Insights API | Chrome UX Report (CrUX) API | |
|---|---|---|
| Category | SEO and site checks | SEO and site checks |
| API key | Needed, free | Needed, free |
| Pricing | Free; a free API key raises the request limits. | Free with a free Google Cloud API key, 150 queries per minute. |
| From the browser | Yes (CORS) | Not stated |
| Formats | Not stated | JSON |
| Interface | REST, HTTP-GET | REST |
| Provider | developers.google.com | developer.chrome.com |
| Last checked | Working on November 1st, 2026 | Working on November 1st, 2026 |
| MCP server | No | No |
Which one to choose
PageSpeed Insights runs a Lighthouse test on any public URL and returns scores, audits and suggestions, plus real-user data when there is some. The Chrome UX Report API only returns real-user Core Web Vitals, as a 28-day average, for pages and sites with enough Chrome visitors, at 150 queries a minute. Use PageSpeed Insights to test and fix a page, CrUX to watch how fast a site really is.
Each service's own page has its full description, a code example and what visitors report: Google PageSpeed Insights API, Chrome UX Report (CrUX) API.