Server-Side Rendering
A technique where web pages are generated on the server for each request, improving initial load time and SEO compared to client-side rendering.
Definition
Server-Side Rendering (SSR) generates complete HTML on the server for each page request, sending fully-formed content to browsers. This contrasts with client-side rendering where browsers receive minimal HTML and JavaScript builds the page locally.
SSR improves initial page load speed (users see content faster), SEO (search engines receive complete content), and performance on lower-powered devices that struggle with JavaScript-heavy pages.
Why It Matters
SSR directly impacts Core Web Vitals and search rankings. Pages that render server-side typically achieve faster LCP scores and better crawlability—both critical for organic traffic.
For content-heavy sites, SSR ensures search engines see the same content users do, eliminating indexing issues that plague client-side rendered applications.
Examples in Practice
An e-commerce site migrates from client-side rendering to SSR, improving time-to-first-meaningful-paint from 3.5s to 0.8s. Conversion rate increases 12% from faster perceived loading.
A JavaScript-heavy application implements SSR to fix SEO issues—search engines previously couldn't index dynamically loaded content. Organic traffic grows 45% after proper indexing.