Core Web Vitals Optimization: The Technical Guide for High‑Performance Websites

Core Web Vitals (CWV) directly influence user experience and rankings. These are the high‑leverage fixes that repeatedly move metrics.

Largest Contentful Paint (LCP)

• Inline critical CSS; lazy‑load the rest with next/dynamic.
• Use next/image with proper sizes; preload the LCP image.
• Self‑host fonts via next/font to avoid FOIT/FOUT.

Cumulative Layout Shift (CLS)

• Reserve space for media with aspect‑ratio boxes.
• Load third‑party widgets after core content; avoid injecting above‑the‑fold elements.

Interaction to Next Paint (INP)

• Reduce main‑thread work; move logic server‑side (RSC).
• Defer non‑critical scripts; remove unused dependencies.

Set performance budgets and monitor with Lighthouse CI and RUM. We can implement it.