Collect real-user speed data for your site

perf.cwv.no_field_data · effort: about an hour

Why it matters

Google has no real-user data for this page or site, usually because too few Chrome visitors have loaded it, so the numbers come from one simulated test. That test is pessimistic and noisy, so use it as a guide and add your own measurements.

The fix

Treat the lab numbers as a direction, not a verdict, and run the test several times. Real-user data appears in Google's reports once enough Chrome visitors have loaded the page, which can take weeks on a small site.
Collect your own real-user data with Google's open-source web-vitals library, and send the values to your analytics tool or to an endpoint you control. Respect your privacy rules and your cookie policy when you do.
Check the Core Web Vitals report in Google Search Console after some time, where it shows the groups of pages that Google has data for.

html

<script type="module">
  import {onCLS, onINP, onLCP} from 'https://unpkg.com/web-vitals@5?module';

  function send(metric) {
    // Replace with a call to your analytics or an endpoint you control
    console.log(metric.name, metric.value);
  }

  onCLS(send);
  onINP(send);
  onLCP(send);
</script>

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Why it matters

The fix

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