PageSpeed vs Core Web Vitals — what matters?

Core Web Vitals (LCP, FID/INP, CLS) are a SUBSET of PageSpeed metrics that Google uses for ranking. PageSpeed shows you a score 0-100; Core Web Vitals shows whether you pass three specific thresholds. For SEO, Core Web Vitals "Good" rating matters more than your overall PageSpeed score. Most failures: images loading too slowly (LCP), JavaScript blocking interaction (INP), and layout shifting as content loads (CLS).