TECHNICAL · SEO GLOSSARY
Server-Side Rendering (SSR)
Generating the full HTML of a page on the server per request, so browsers and crawlers receive complete content on the first HTTP response — the opposite of client-side rendering (CSR) where a JavaScript bundle builds the DOM after load.
Definition
Server-side rendering (SSR) means the web server executes the page logic and produces complete HTML before sending a response to the browser. When Googlebot (or any crawler) fetches the URL, it receives a fully-formed HTML document with all content, metadata, and structured data already present — no JavaScript needs to execute first. Contrast with client-side rendering (CSR/SPA): the server returns a near-empty HTML shell (`<div id="root"></div>`) and a JavaScript bundle; the browser must download, parse, and execute the JS before page content appears. Googlebot can render JavaScript, but it enters a second-wave rendering queue that can delay indexing by days or weeks, and it does not execute JS in the same context as a browser.
Why it matters for SEO
SSR eliminates the JS rendering risk: content is available to crawlers immediately, Core Web Vitals (especially LCP and FCP) improve because the browser doesn't wait for JS execution before rendering above-the-fold content, and structured data embedded in the server response is read reliably by AI crawlers that don't execute JavaScript. Modern frameworks support SSR natively: Next.js (App Router default), Nuxt, SvelteKit, Remix, and Astro all server-render by default. Vite, Create React App, and bare React/Vue are CSR by default and require explicit SSR configuration.
How DeepSEOAnalysis checks this
The audit fetches each crawled URL with JavaScript disabled (simulating a basic crawler pass) and compares the visible content and structured data in the raw HTML response against the fully-rendered DOM. Pages where significant content, H1s, metadata, or JSON-LD are absent from the raw HTML are flagged as client-side rendered with specific recommendations for the detected framework.
Useful tools and resources
GLOSSARY
Related terms
technical
JavaScript Hydration
The process where a framework (React, Vue, Svelte) takes server-rendered HTML and attaches JavaScript event listeners and state to make it interactive — a gap in this process can leave content visible to users but not readable by crawlers, or cause CLS.
Read definition →performance
Core Web Vitals
Three Google metrics — LCP, INP, and CLS — that measure real-user loading, interactivity, and visual stability.
Read definition →structured data
FAQPage Schema
JSON-LD structured data that marks Q&A pairs on a page so search engines and AI systems can display and cite them directly.
Read definition →technical
Rendering SEO
How search engines process JavaScript-heavy pages — client-side rendering (CSR) delays indexing; server-side rendering (SSR) or static generation (SSG) makes content immediately available to crawlers.
Read definition →See how your site scores on Server-Side Rendering (SSR).
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