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What Is JavaScript Rendering?

JavaScript rendering is the process of executing a page's JavaScript so that dynamically loaded content becomes visible and extractable, as opposed to relying only on the initial static HTML.

Client-side vs. server-side rendering

Client-side rendered pages send a minimal HTML shell and load content via JavaScript in the browser. Server-side rendered pages send fully built HTML from the start. Scraping client-side rendered sites requires a rendering engine, such as a headless browser, to see the final content.

Why it matters for scraping accuracy

Skipping JavaScript rendering on a dynamic site often means missing prices, reviews, or listings that only appear after scripts run. Reliable data delivery depends on correctly detecting which pages need rendering and which don’t, to keep both accuracy and speed in balance.