Core Web Vitals and performance budget monitor for developers. Track LCP, INP, CLS, set budgets, and ship fast sites.
Real-time LCP, INP, and CLS measurement with color-coded scores using Google's official thresholds. Know exactly where you stand.
FREEA single 0-100 score based on Core Web Vitals weighting. See the score at a glance on the extension badge.
FREETTFB, First Contentful Paint, DOM Content Loaded, and Page Load time. All the timings you need in one view.
FREESee resource count and transfer size grouped by type: scripts, stylesheets, images, fonts, and XHR. Spot bloat instantly.
FREETotal transfer size of all resources at a glance. Know if your page is lean or loading megabytes of unnecessary assets.
FREESimplified timeline visualization of resource loading. See which resources are slow and where they overlap in the loading timeline.
PROSet thresholds for LCP, INP, CLS, TTFB, page weight, and resource count. Get instant visual warnings when budgets are exceeded.
PROStore the last 10 page loads per domain. Track how performance changes over time as you optimize your site.
PROExport the full performance report including all metrics, resource entries, and timings as structured JSON for analysis.
PROAnalyze which third-party domains load the most resources and add the most weight. Identify performance-killing external scripts.
PROWeighted scoring breakdown showing how each Core Web Vital contributes to your overall score. Prioritize what to fix first.
PROPure browser Performance API. No external scripts, no data sent to servers. Your performance data stays in your browser.
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