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LCP Test

Lab Largest Contentful Paint against the Core Web Vitals thresholds.

Runs a real Chromium page load — usually takes 5–15 seconds.

What this tool checks

  • Largest Contentful Paint

    Lab measurement of Largest Contentful Paint against the Core Web Vitals thresholds (good ≤ 2500ms, poor > 4000ms).

    Why it matters: LCP marks when the main content becomes visible. Slow LCP makes the page feel unresponsive. This is a lab measurement from a single automated load — it is not real-user (field) data and will differ from Chrome UX Report values.

    If it fails: Optimise the LCP element: serve a right-sized, modern-format image, remove render-blocking resources, and use a fast server/CDN.

    Source: web.dev/articles/lcp

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