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Web Vitals

Core Web Vitals (LCP, CLS, INP, FCP, TTFB) collected by the same script, at no extra cost.

What is measured

The same script that counts pageviews also reports Google's Core Web Vitals, so you see how the site feels, not only how many people felt it. No extra tag, no extra cost: vitals never count against your plan.

MetricWhat it captures
LCPLargest Contentful Paint: when the main content became visible.
CLSCumulative Layout Shift: how much the page jumped around.
INPInteraction to Next Paint: how quickly the page reacted to input.
FCPFirst Contentful Paint: when anything first rendered.
TTFBTime To First Byte: how fast the server answered.

How it reports

Each metric is measured the way Google defines it (CLS as the session-window maximum) and reported once per pageview, when the tab first goes to the background, with Google's own good/needs-improvement/poor thresholds attached. The dashboard shows the distribution per page, so a slow route stands out instead of drowning in a site-wide average.

Reading it

Vitals arrive with normal traffic; a page needs real visits before its numbers stabilize. If a route looks slow, the dashboard page explains how to cut the range and compare periods to see whether a deploy moved it.