The Next.js performance checklist we use on every launch

Performance is a feature. Faster pages rank better, convert better and cost less to serve. This is the checklist we run before every launch.

Rendering

• Prefer static generation and ISR for marketing pages; render dynamically only what's personal.
• Keep client components at the leaves. Server Components ship zero JavaScript.
• Lazy-load heavy, below-the-fold experiences like 3D scenes and charts.

Images & fonts

• Use next/image with explicit sizes and modern formats.
• Load fonts with display: swap and subset them.
• Make sure the LCP element is text or a priority image, never a canvas.

JavaScript

• Audit bundles. A single heavy dependency can undo all your work.
• Defer analytics until after consent and after the page is interactive.

Measure in the field

Lab scores are a starting point. Track Core Web Vitals from real users and fix regressions in CI.

Fast by default, measured continuously: that's the standard.