Core Web Vitals: The Developer's Practical Guide

Google's Core Web Vitals directly affect your search rankings. Here's what actually moves the needle after testing on 10+ production sites.

LCP: Largest Contentful Paint

Preload your hero image with <link rel="preload">. Use modern formats (AVIF/WebP). Avoid lazy-loading above-the-fold images.

CLS: Cumulative Layout Shift

Always set explicit width/height on images and embeds. Reserve space for ads and dynamic content with CSS aspect-ratio.

INP: Interaction to Next Paint

Break up long tasks with scheduler.yield(). Defer non-critical third-party scripts.