LCP — loading
Largest Contentful Paint measures main-content loading. Good: 2.5 seconds or less at the 75th percentile.
Signaux Web essentiels
Les mesures de Google basées sur l'usage réel pour la vitesse de chargement, la réactivité et la stabilité visuelle.
En termes simples
Core Web Vitals measure loading, responsiveness, and layout stability using real-user data when enough is available.
Lab tests help diagnose issues; field data reflects real visits. These metrics cannot guarantee rankings or overall quality.
Les fondements
What matters in Core Web Vitals
INP — responsiveness
Interaction to Next Paint measures responsiveness. Good: 200 milliseconds or less at the 75th percentile.
CLS — stability
Cumulative Layout Shift measures unexpected movement. Good: 0.1 or less at the 75th percentile.
Appliqué par The Forge
Comment nous le mettons en pratique
We use these measures to reduce waiting and keep pages responsive and stable.
Deliver the important content early
Use server rendering, caching, optimised images, and deliberate loading priorities.
Keep interactions responsive
Limit JavaScript and long tasks so controls respond quickly.
Reserve visual space
Reserve media dimensions and manage font loading to reduce layout shifts.
Measure lab and field data
Use lab tests to diagnose issues and field data to understand real visits.
Une limite utile
Les limites à garder en tête
- Core Web Vitals are not the same thing as a Lighthouse performance score.
- Passing the thresholds does not guarantee rankings, conversions, or a satisfying overall experience.
- A single local test cannot represent the range of real devices, networks, pages, and visitors.
Un exemple concret
A stable service landing page
A service page loads its main content early, reserves image space, and responds quickly. Field data checks the experience of real visitors.
Pour aller plus loin
Sources principales
Consultez les sources de ces explications.
Concept associé
Analytics & conversions: Analytique et conversions
Mesurer l'utilisation d'un site dans le respect des choix des visiteurs afin de comprendre ce qui les aide à passer à l'étape suivante.