What is Core Web Vitals?
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Core Web Vitals are a set of specific metrics Google uses to measure real-world user experience on a web page — how fast it loads, how quickly it responds to interaction, and how stable it is visually while loading. They’re part of Google’s page experience signals, meaning they directly influence how a site ranks, not just how it feels to use.
There are three Core Web Vitals, each capturing a different aspect of experience:
- LCP (Largest Contentful Paint) — loading speed; how long until the main content appears. Target: under 2.5 seconds.
- INP (Interaction to Next Paint) — responsiveness; how quickly the page reacts to a click or tap. Target: under 200ms. INP replaced FID (First Input Delay) as a Core Web Vital in 2024.
- CLS (Cumulative Layout Shift) — visual stability; how much the layout jumps around as it loads. Target: under 0.1.
Core Web Vitals matter because they combine ranking impact with real business impact. A slow or unstable page frustrates users, raises bounce rates, and lowers conversion — and because Google measures these on actual visitor data (field data), poor scores can hold back rankings even for otherwise well-optimized content. Passing them is a baseline expectation, not a bonus.
On ecommerce platforms, and Magento (Adobe Commerce) in particular, INP is often the hardest to pass — heavy JavaScript frontends make filters and interactions lag. The usual fixes are full-page caching, a CDN, optimized images (WebP/AVIF), lazy-loading, and up-to-date PHP and database versions. The structural fix on Magento is a lightweight frontend like Hyvä, which replaces the legacy theme stack and lets most stores hit green vitals without endless patching. Improving Core Web Vitals is a core part of technical SEO and, increasingly, AI-search visibility.
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