Hydration
Definition
Hydration is the process of attaching client-side JavaScript to server-rendered HTML so a static page becomes an interactive application.
By Vinespire Editorial Team, Editorial ·
This term is part of the full AI search glossary.
Full definition
After SSR or static generation delivers HTML, frameworks re-run components in the browser, bind event listeners, and reconcile the DOM. Until hydration finishes, some controls may not respond. Excessive hydration work hurts Interaction to Next Paint.
Partial or selective hydration strategies load interactivity only where needed. Mismatches between server and client markup cause warnings, flicker, or broken UI.
SEO-relevant text should live in the pre-hydration HTML whenever possible so crawlers and AI fetchers do not depend on client execution. See Server-Side Rendering and INP.