Core Web Vitals
Lighthouse Viewer
Run a live Lighthouse audit or upload a report to explore performance, accessibility, SEO and best-practice scores in one dashboard.
No report loaded yet — upload a Lighthouse JSON or run one.
About this tool
Comprehensive documentation & audit utility guideThe Lighthouse Viewer runs Google's actual Lighthouse engine — the same tool behind PageSpeed Insights and Chrome DevTools — against a live URL, using a real headless Chrome instance in a dedicated cloud function. You can also upload an existing Lighthouse JSON report to explore it without re-running an audit.
How it works
1
Enter a URL
Or upload a Lighthouse JSON report you already have.
2
Chrome runs the audit
A real headless Chrome instance loads the page and Lighthouse measures it.
3
Explore the results
Scores, Core Web Vitals, opportunities and diagnostics in one dashboard.
What it checks
Performance, Accessibility, Best Practices and SEO category scores
Core Web Vitals: Largest Contentful Paint, Cumulative Layout Shift, Total Blocking Time
Opportunities (specific ways to improve) and diagnostics
Network requests, console errors, third-party impact and more
