Web Vitals
Core Web Vitals (LCP, CLS, INP, FCP, TTFB) collected by the same script, at no extra cost.
Speed, from the same script
The 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. There is no extra tag and no extra cost: vitals never count against your plan.
What is measured
| Metric | What it captures | Good |
|---|---|---|
| LCP | Largest Contentful Paint: when the main content became visible. | ≤ 2.5s |
| CLS | Cumulative Layout Shift: how much the page jumped around. | ≤ 0.1 |
| INP | Interaction to Next Paint: how quickly the page reacted to input. | ≤ 200ms |
| FCP | First Contentful Paint: when anything first rendered. | ≤ 1.8s |
| TTFB | Time To First Byte: how fast the server answered. | ≤ 800ms |
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 well
Give a page real traffic first
Vitals arrive with normal visits, so a page needs a decent sample before its numbers settle. If a route looks slow, the dashboard page explains how to cut the range and compare periods, so you can tell whether a deploy moved it or it was always that way.