Most teams still treat Core Web Vitals as a Lighthouse score to chase. That's the trap. Lab scores are a proxy; field data is the ranking signal. Here's what each metric demands in 2026 and where the real wins hide.
LCP: it's almost always the hero image
Largest Contentful Paint is dominated by one element on most pages. Find it, preload it, and stop shipping a 1.4 MB PNG where a 90 KB AVIF would do.
<link rel="preload" as="image" href="/hero.avif" fetchpriority="high" />INP replaced FID — and it's harder
Interaction to Next Paint measures the whole interaction, not just the first input delay. Long tasks on the main thread are the enemy.
If a third-party tag blocks the main thread for 300ms, that's your INP budget gone before your code even runs.
CLS: reserve space for everything
Set width/height on media, reserve space for ads and embeds, and never inject content above existing content after load.
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We tune LCP, INP and CLS to "Good" on real sites — measured in Search Console, not just Lighthouse.
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