Performance6 min read

Web Performance in 2025: What Actually Matters

Core Web Vitals changed the game. But with Google's latest ranking signals, are you still measuring the right things? Here is what actually impacts your users and your rankings.

Jordan Kim

SEO & Growth Strategist

April 21, 2025

PerformanceSEOCore Web Vitals

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Google's Core Web Vitals have been a ranking signal since 2021, but the goalposts keep shifting. In 2025, Interaction to Next Paint (INP) has replaced First Input Delay as the interactivity metric, and the thresholds for "good" scores have tightened.

The Three Metrics That Actually Move Rankings

Largest Contentful Paint (LCP) — target under 2.5s
Cumulative Layout Shift (CLS) — target under 0.1
Interaction to Next Paint (INP) — target under 200ms

LCP: The Biggest Win Is Usually the Image

In most cases, the LCP element is your hero image. Adding fetchpriority="high" to it, serving it from a CDN, and preloading it in your <head> can cut LCP by 40-60% without touching a single line of JavaScript.

INP: The Hidden Killer in 2025

Most sites that fail INP are not slow to load — they are slow to respond. Cause: JavaScript blocking the main thread during user interactions. The fix is moving heavy computations off the main thread with Web Workers, and breaking up long tasks into smaller schedulable chunks.

“Performance is not a feature. It is the foundation everything else rests on.”

Quick Wins Checklist

Use <link rel="preconnect"> for Google Fonts and analytics scripts
Defer third-party scripts (chat widgets, heatmaps) until after load
Compress images with Squoosh or Sharp before shipping
Eliminate render-blocking CSS by inlining critical styles
Enable HTTP/2 or HTTP/3 on your host

Jordan Kim

SEO & Growth Strategist

Part of the WebQore team building conversion-focused digital experiences for growing brands. Passionate about design, performance, and measurable outcomes.