Google's three real-user speed and stability metrics — how fast the main content loads, how quickly the page responds to input, and how much it visually shifts — used as a ranking signal.
Core Web Vitals are the page-experience metrics Google measures from real Chrome users: LCP (Largest Contentful Paint — how long the biggest element takes to appear), INP (Interaction to Next Paint — how fast the page reacts when someone taps or clicks), and CLS (Cumulative Layout Shift — how much the layout jumps around while loading). Each has a clear threshold: good, needs improvement, or poor.
They matter for SEO because they're a confirmed Google ranking factor, and they matter for conversion because a slow, janky page loses visitors before they read a word. A page can be perfectly crawlable and well-written but still underperform because its hero image isn't sized, its scripts block rendering, or an ad slot shoves the content down as it loads.
CommandSEO measures Core Web Vitals against Google's thresholds and turns a poor score into a plain-English fix — "LCP is 4.2s on mobile; the hero image has no width/height and isn't preloaded" — rather than a number you're left to interpret.
What to do about it
Treat a poor LCP or CLS as a real ranking issue, not a vanity metric. Size and preload your largest image, defer non-critical JavaScript, and reserve space for images and embeds so nothing shifts. Then re-verify the page to confirm the metric actually improved.
Common questions
What are good Core Web Vitals scores?
LCP under 2.5s, INP under 200ms, and CLS under 0.1 are "good." Above 4s LCP, 500ms INP, or 0.25 CLS is "poor" and worth fixing first.
Do Core Web Vitals affect SEO?
Yes. They're part of Google's page-experience ranking signals. They rarely outweigh relevance and links, but on close calls a faster, more stable page wins — and they directly affect conversion regardless of ranking.