1. What is Client-Side Rendering (CSR)?

Client-Side Rendering is the process of rendering only a bare-bones HTML page on the server with the complete page render happening on the browser by downloading and executing all the necessary JavaScript

  • traditionally used in *Single-Page Applications (SPAs)

2. How does Client-Side Rendering (CSR) work?

How does client-side rendering work
  1. first the client sends a GET request to the server
  2. then the server responds with a bare-bones HTML page
  3. the client renders it
  4. downloads, parses and executes the JavaScript bundle to boot up the app
  5. which will fetch any data needed
  6. to finally re-render the complete app

3. What are the Pros and Cons of Client-Side Rendering (CSR)?


  • clear separation between client and server code
  • interactive app after first load:
    • navigation with less data and no refresh -> faster and more responsive app
    • data fetched on client uses bandwidth, but can be cached -> turn a site into a Single Page Application (SPA)


  • slow loading times
    • slow first load, worse with bigger JS bundles, which are increasing
    • complete HTML cannot be cached
    • data fetching might delay interactions depending on size
  • SEO considerations
    • crawlers might not run JS, possibly harming SEO
  • code duplication
    • clear separation between client and server code can lead to duplication

4. When should you use Client-Side Rendering (CSR)?

  • when slow initial first load is not a problem
  • when you need a complex site with a lot of interactivity
  • when you need navigation without full page reloads
  • when SEO is not a top priority

Perfect for anything you would call an app, for example games, editors and other complex software


Full Video on YouTube

Client-side Rendering
Render your application’s UI on the client
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Client-side vs. server-side rendering: why it’s not all black and white
Since the dawn of time, the conventional method for getting your HTML up onto a screen was by using server-side rendering. It was the only way. You loaded up your .html pages on your server, then your server went and turned them into useful documents on your users’ browsers. Server-side