Core Web Vitals Checker
Read the real-world LCP, INP, and CLS experienced by Chrome users, with current and historical CrUX data.
Measure real-user performance, isolate bottlenecks, optimize delivery, and model the business impact—all without leaving the SpeedVitals workflow.
Choose your instrument
Read the real-world LCP, INP, and CLS experienced by Chrome users, with current and historical CrUX data.
Audit up to 500 URLs together and turn site-wide field data into a clear optimization queue.
Compress, resize, and convert images locally to AVIF, WebP, JPEG XL, and other modern formats.
Compare CDN response times across providers, regions, percentiles, and historical windows.
Translate an LCP improvement into projected conversion lift, monthly gain, and annual net value.
Inspect request waterfalls, payload weight, status codes, and bottlenecks without uploading your HAR file.
Extract above-the-fold styles for the viewports that matter and reduce render-blocking CSS.
Verify QUIC, Alt-Svc, ALPN, DNS, and transport support instead of trusting a single response header.
Not sure where to begin?