Concepts
Sentiment Score How Witnes grades each session as Good, Meh, or Bad based on a combination of performance symptoms. Traffic Metrics How Page Loads, Unique Visitors, and Sessions are defined, counted, and relate to each other. Feature Status What's live in Traffic Analytics today and what's on the roadmap.
Metrics
TTFB Time to First Byte — how long the server takes to respond. FCP First Contentful Paint — first user-visible signal the page is loading. DOM Interactive Time until HTML is parsed and the DOM is ready for interaction. LCP Largest Contentful Paint — the primary measure of perceived load speed. CLS Cumulative Layout Shift — how much the page layout moves unexpectedly during load. Overall Health Combined LCP + CLS pass/fail score reported for each page load.