There are three Core Web Vitals that Google uses as official ranking signals. Largest Contentful Paint (LCP) measures loading performance and should occur within 2.5 seconds of when the page first starts loading. First Input Delay (FID) measures interactivity, specifically the time from when a user first interacts with your page to when the browser can actually respond to that interaction, with a target under 100 milliseconds. Cumulative Layout Shift (CLS) measures visual stability by quantifying unexpected layout shifts during the page's lifespan, with a score under 0.1 being ideal. Starting March 2024, FID is officially replaced by Interaction to Next Paint (INP) as the Core Web Vital for responsiveness. INP is more comprehensive because it considers all page interactions rather than just the first one, with a good score being 200 milliseconds or less. This change matters because INP catches sluggish interactions that FID might miss on complex pages with heavy JavaScript. These three metrics are part of Google's broader Page Experience signals but are the only ones explicitly called Core Web Vitals. Other metrics like Time to First Byte (TTFB), First Contentful Paint (FCP), and Total Blocking Time (TBT) matter for performance but aren't Core Web Vitals themselves. They often correlate though—fixing a slow TTFB usually improves LCP. At Ottawa SEO Inc., we track Core Web Vitals through Google Search Console's dedicated report and supplement with PageSpeed Insights for lab data. The Search Console data is field data from real Chrome users visiting your site, which is what Google actually uses for rankings. We typically see the biggest LCP improvements from optimizing images and server response times, INP gains from reducing JavaScript execution and breaking up long tasks, and CLS fixes from setting explicit dimensions on images and ads. The practical reality is that Core Web Vitals are a tiebreaker signal, not a primary ranking factor. A site with mediocre vitals but superior content will usually outrank a fast site with thin content. But when you're competing in saturated niches like legal services or real estate in Ottawa or Toronto, passing all three thresholds can be the edge that pushes you from position four to the featured snippet.