Core Web Vitals are Google’s way of measuring how a page feels to real visitors: how fast the main content appears, how quickly the page responds, and whether things jump around while it loads.
Largest Contentful Paint (LCP)
LCP measures how long it takes for the biggest visible element — usually a hero image or headline — to render. Google’s “good” threshold is 2.5 seconds or less.
Common fixes: compress and correctly size the hero image, don’t lazy-load it, preload your main font, use a good host and a CDN, and remove render-blocking scripts.
Interaction to Next Paint (INP)
INP measures how quickly the page responds when someone taps, clicks or types. A “good” score is 200 milliseconds or less.
Common fixes: ship less JavaScript, remove unused plugins and third-party widgets, defer non-essential scripts, and break up long tasks.
Cumulative Layout Shift (CLS)
CLS measures unexpected movement — like a button jumping down just as you tap it because an ad loaded above it. A “good” score is 0.1 or less.
Common fixes: set width and height on images and videos, reserve space for ads and embeds, and avoid inserting banners above existing content.
How to measure your own site
- PageSpeed Insights shows both lab data and real-user field data.
- Google Search Console groups your URLs by Core Web Vitals status.
- Chrome DevTools helps you find exactly which element or script is slow.
Where to start
Fix the template, not the page. One improvement to your header, fonts or image handling improves every page that shares it. This theme is built with that in mind: self-hosted fonts, no jQuery, one stylesheet and deferred scripts.
