A slow page costs you visitors, and visitors who leave do not call or buy. Google also measures how fast your pages load, how quickly they respond, and how much they jump around, and it uses those numbers in ranking.
Core Web Vitals are the three numbers Google watches: how fast your main content appears (LCP), how fast the page reacts when someone clicks (INP), and how much the layout jumps around (CLS). If a page fails any one of them, it does not pass Google's check.
We test your homepage with Google PageSpeed Insights on mobile. That is a lab test, not data from your real visitors. It measures LCP and CLS directly. INP needs real visitors, so we use Total Blocking Time, the lab number that tracks it most closely. Then we show you what is slowing things down and what to fix first.
