Performance
Largest Contentful Paint (LCP)
Time until the largest above-fold element renders — usually the hero image or H1. ≤2.5s at the 75th percentile is the `good` threshold; >4s is poor.
What it is
Largest Contentful Paint — measures when the largest image, video poster, or block-level text element in the viewport finishes rendering. The reference Core Web Vital for perceived load speed. Field data preferred (CrUX); `lab` data via Lighthouse is a fallback that doesn't capture real-network variance.
Why it matters
LCP correlates with bounce rate more cleanly than any other metric. The usual culprits — unoptimized hero images, render-blocking CSS, late-injected fonts, slow TTFB — are all fixable, and almost every fix has a 1:1 conversion-rate impact on commerce sites.
Who it applies to
Every public-facing site.
How WQI scores it
Web Quality Index considers this standard satisfied when the supporting factor passes.
| # | Factor | Status |
|---|---|---|
| 8 | Mobile PageSpeed score + Core Web Vitals (LCP, FCP, CLS) | live |
Related standards
- See also
- CWV , INP , Resource hints , WebP / AVIF , font-display
Standards that share factors with this one
Auto-computed from overlapping factor tickets in satisfiedBy, excluding standards already listed under "See also" above. Strong overlap suggests these standards rise and fall together when sites are scored.
Other references
- guidance web.dev — Optimize LCP
- tooling Chrome User Experience Report (CrUX)