Google's ranking signals keep shifting. Here's what we've learned optimising dozens of high-traffic sites this year.
Core Web Vitals became a confirmed Google ranking factor in 2021. In 2025, they're still relevant — but the thresholds have tightened, the metrics have evolved, and the tooling has improved dramatically. Here's what actually matters for your site's performance score and organic ranking.
In 90% of audits we run, the LCP element is either a hero image or a large heading. The fastest fix: preload the LCP image with a link rel=preload tag, serve it in WebP or AVIF format, and ensure it's not lazy-loaded. These three changes alone routinely drop LCP by 800ms–1.5s.
INP measures the latency of every interaction on the page — clicks, taps, keyboard inputs — and reports the worst-case outcome. Long JavaScript tasks on the main thread are the primary culprit. Break up blocking scripts with setTimeout or scheduler.postTask, and defer anything not needed for the initial render.
Third-party scripts (chat widgets, analytics tags, ad networks) are the silent killers of INP scores. Audit your tag manager payload quarterly.
Even in 2025, layout shift caused by late-loading fonts, images without explicit dimensions, and dynamically injected content remains common. The fix is structural: always set explicit width and height on images, use font-display: optional for non-critical fonts, and reserve space for dynamic content with CSS aspect-ratio or min-height.