Making WordPress fast: a Core Web Vitals playbook

Most WordPress sites are slow for the same handful of reasons. The good news: every one of them is fixable, and you rarely need to rebuild from scratch to get there.

Start with a measurement, not a guess

Before changing anything, capture a baseline with a lab tool and real-user data. We look at three numbers:

• LCP (Largest Contentful Paint): how quickly the main content appears.
• INP (Interaction to Next Paint): how responsive the page feels.
• CLS (Cumulative Layout Shift): how much the layout jumps around.

Write these down. You can’t tell whether a change helped without a before and after.

The high-leverage fixes

1. Ship less JavaScript. Page builders are the usual culprit. A lean custom theme with native blocks removes most of it.
2. Right-size and lazy-load images. Serve modern formats, set explicit width/height to kill layout shift, and only eager-load the hero.
3. Cache aggressively at the edge. A full-page cache in front of PHP turns a 600ms response into 20ms.
4. Load fonts without blocking. Preconnect, font-display: swap, and subset to the characters you actually use.

The result

On a typical rebuild we take LCP from 3 to 4 seconds down to well under one, and move every Core Web Vital into the green. Faster pages rank better and convert better, and the work pays for itself.

Want us to audit your site? Book a call and we’ll send you a fixed quote.