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Web vitals

Core Web Vitals from real visits, measured by the same script. No extra tag.

Updated 21 Oct 2026

What's measured

The script measures five metrics on every page and sends them once, when the visitor leaves or switches tabs. Reports show the 75th percentile (p75), the same figure Google uses.

LCPLargest contentful paint. Good under 2.5 s, poor over 4 s.
INPInteraction to next paint, the slowest interaction. Good under 200 ms, poor over 500 ms.
CLSCumulative layout shift. Good under 0.1, poor over 0.25.
FCPFirst contentful paint. Good under 1.8 s, poor over 3 s.
TTFBTime to first byte. Good under 800 ms, poor over 1.8 s.

Reading the report

  • Each metric shows p75, its grade, and the share of visits that were good, needing work, or poor.
  • The All, Mobile and Desktop switch shows each metric's p75, good share and number of visits for that device.
  • Each card shows the change in p75 against the previous period of the same length (lower is better).
  • The trend chart has tabs for LCP, INP, CLS and TTFB, with a mobile and a desktop line per day.
  • The pages table lists p75 per page. If you can see revenue, it's sorted by revenue from visits that landed there, so you fix the pages that earn first.

Browsers that don't support a metric (INP in Safari, for example) simply don't send it, so sample counts differ per metric.

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