Core Web Vitals Field Guide

Core Web Vitals Field Guide: LCP, CLS, INP Explained

Core Web Vitals are Google's way of measuring whether a website actually feels fast and stable to real users. They are a real ranking factor — but more importantly, they are a real conversion factor.

Three metrics: Largest Contentful Paint, Cumulative Layout Shift, and Interaction to Next Paint. Each measures a different dimension of user experience.

The three Core Web Vitals

  • Largest Contentful Paint (LCP): time until the biggest visible element loads — target under 2.5 seconds
  • Cumulative Layout Shift (CLS): how much page content jumps around as it loads — target under 0.1
  • Interaction to Next Paint (INP): time from user interaction to visual response — target under 200ms
  • First Contentful Paint (FCP): time until anything visible loads — should be under 1.8s
  • Time to First Byte (TTFB): server response time — should be under 800ms
  • Total Blocking Time (TBT): JavaScript execution blocking the main thread

The fastest way to improve Core Web Vitals

For most service business sites, three changes deliver 80% of the improvement: compress hero images to under 100KB, defer non-critical JavaScript, and reserve space for images and ads to prevent layout shift. Everything else is incremental.

For agency-grade help across the Dallas, Frisco, and Colorado Springs markets, fasthippomedia.com offers the full range of services this guide describes — from technical SEO to local rankings to conversion-focused web design.

Bottom line

Run your site through PageSpeed Insights once a month. Fix any red metric immediately. Yellow metrics are next-quarter priorities.

Further reading: Google's web.dev Core Web Vitals reference.


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