Core Web Vitals explained for non-developers
Last reviewed 19 May 2026 · Growth Check editorial team
Core Web Vitals are three metrics Google uses as a ranking factor. They measure how fast your page feels to a real user, not how fast it loads in theory.
LCP — Largest Contentful Paint
How long it takes for the biggest visible element (usually your hero image) to appear. Google's "Good" threshold is under 2.5 seconds. Most UK SMB sites are at 3–6 seconds.
Fix: compress images, use modern formats (WebP/AVIF), preload the hero image, fix slow hosting.
INP — Interaction to Next Paint
How responsive your page feels when someone clicks or taps something. Replaced the old "FID" metric in 2024. Good threshold: under 200ms.
Fix: reduce JavaScript bloat, defer non-essential scripts, audit third-party scripts (chat widgets, analytics).
CLS — Cumulative Layout Shift
How much the page jumps around as it loads (annoying when you go to click a button and it moves). Good threshold: under 0.1.
Fix: specify width/height on images, reserve space for ads and embeds, avoid late-loading fonts.
How to check yours
Google Search Console → Core Web Vitals. Or run any page through PageSpeed Insights.