Google Core Web Vitals & Speed Checker
Measure real Google Core Web Vitals (LCP, INP, CLS, FCP) on mobile and desktop using official Google Lighthouse diagnostics without hallucinations.
Overview & Why This Matters
Google's Core Web Vitals are official ranking signals that quantify real-world user experience: loading performance (LCP), interactivity responsiveness (INP), and visual layout stability (CLS). Passing these thresholds improves both search rankings and visitor conversion rates.
Why Core Web Vitals Directly Impact Organic Rankings
Direct Google Search Ranking Signal
Core Web Vitals are integrated into Google's Page Experience ranking algorithm, boosting fast, responsive websites above slow competitors.
Maximize Mobile Interactivity (INP)
Interaction to Next Paint (INP) ensures buttons, dropdowns, and mobile checkout flows respond instantly without freezing.
Eliminate Layout Shifting (CLS)
Cumulative Layout Shift prevents frustrating layout jumps that cause users to click the wrong link or abandon transactions.
Core Web Vitals Code Optimizations
Apply these HTML and CSS practices to pass Google Lighthouse and CrUX assessments:
<!-- 1. Preload LCP hero image with high priority -->
<link rel="preload" as="image" href="/hero.webp" fetchpriority="high" />
<!-- 2. Set explicit image dimensions to prevent CLS -->
<img src="/logo.webp" width="240" height="60" alt="Company Logo" />
<!-- 3. Defer non-critical scripts to protect INP -->
<script src="/analytics.js" defer></script>