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Real-user vitals

Core Web Vitals measured on your real visitors' devices, the field data Google actually ranks on.

Measure LCP, INP, CLS, FCP and TTFB on real devices. Add this second script alongside the standard snippet. It loads separately so your core tracker stays tiny, and batches every metric into a single beacon. To keep cost low, vitals are sampled at ~25% of pageloads (more than enough for accurate p75s), and those sampled beacons count toward your event quota. Tune it with data-sample-rate, for example "0.1" for 10%, or "1" to capture every load.

index.html

<script defer
  data-website-id="YOUR_WEBSITE_ID"
  data-sample-rate="0.25"
  src="https://www.jamp.io/app.js">
</script>

Results appear under Monitor → Real-User Vitals, reported as p75 (the 75th percentile Google uses) per page, so a single slow outlier doesn't distort your numbers. Lab-based scores can't see this. Only your actual visitors can.

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