Client-Side Rendering (CSR)
Client-side rendering is when a page ships minimal HTML and builds its content in the browser with JavaScript, which can hide that content from AI crawlers that don't execute scripts.
Also known as: CSR
Client-side rendering builds the page in the visitor's browser. The server sends a near-empty HTML shell plus JavaScript, and the browser then fetches data and assembles the content. It's common in single-page apps — and it's a frequent, silent AEO killer.
The problem for the access pillar is that many AI crawlers read raw HTML and don't run JavaScript, so with pure CSR they receive the empty shell and miss your content entirely. Even crawlers that can render JS often do so inconsistently or skip it under load. The fix is to deliver real content in the initial HTML via server-side rendering or static generation, reserving client-side behavior for genuine interactivity rather than core content.
Example. "View source" on a CSR page often shows just <div id="root"></div> and a
script bundle — no article text. That's exactly what a non-rendering crawler sees, which
is why CSR-only content frequently goes uncited.
Relevant pillar
Related terms
- Server-Side Rendering (SSR)Server-side rendering is when a web server generates a page's full HTML for each request and sends it ready-to-read, so content is present immediately for both browsers and AI crawlers.
- HydrationHydration is the process where JavaScript attaches interactivity to server-rendered HTML in the browser, letting a page be both crawlable as text and interactive for users.
- First Contentful Paint (FCP)First Contentful Paint is a performance metric measuring how long after navigation the browser renders the first piece of page content, used as a proxy for how quickly a page becomes useful.