Web performance: what to fix first

Performance isn’t just about scores. Every extra second hurts conversions and SEO. These are the highest-impact items I apply to every project.

1. Measure before optimizing

Don’t guess. Use Lighthouse, WebPageTest, or Chrome DevTools to find the real bottleneck. Usually 1–2 issues cause 80% of the problem.

JS is the most expensive thing to download and process. Remove or defer unneeded scripts, and lazy-load anything below the fold.

WebP/AVIF, sensible compression, correct dimensions, loading="lazy". Small wins that add up enormously.

When possible, ship static HTML instead of client-side rendering. That’s why frameworks like Astro exist.

Correct HTTP caching headers and a CDN. Roughly 90% of web load time is network — caching avoids it.

Start by measuring, tackle the top 3 issues, then measure again. Repeat that loop and you’ll reach sustainably fast pages.