When you build a website, you have to choose how pages are displayed to users. For this many people turn to two different paths and those are Client-side Rendering (CSR) and Server-side Rendering (SSR). They can improve your site’s loading time and affect how Google and similar search engines see your site and how people use the website. Next.JS which is a popular React framework, makes things simpler to use any of these.

These concepts are explained clearly in this blog, along with a brief FAQ sections to clear up doubts that many of you might have.

What is Rendering?

Rendering is similar to showing your code as a picture that appears on users’ screens. It can occur in two different locations.

• Server: A machine in another location that makes the page for you.

• Client: The browser such as Chrome or Firefox, that the user uses to see the page.

The location of your rendering process determines your site's loading speed, ease to find it in search engines and its interactivity.

Key Points:

• Client-side Rendering (CSR), renders pages in the browser with the help of JavaScript. As a result, the first time you visit a page may be slower, but your next visit will be faster.

• It appears that Server-side Rendering (SSR) generates HTML on the server which results a faster experience and better SEO.

• Next.JS is able to handle both CSR and SSR, so that developers can pick according to their project needs like SEO or interactivity.

• Next.JS users can also choose Static Site Generation (SSG) which pre-renders pages to make them faster.

Whether to use CSR or SSR is influenced by performance and SEO. There is no one fit for all problems.

Client-side Rendering (CSR)

The browser does the work in CSR. A simple page with JavaScript is sent by the server. A browser uses this information to get data and construct the page. Picture yourself getting a pizza kit delivered. You buy the dough and toppings, but you put it in the oven yourself.

• Pros: Apps that require interaction such as chat or dashboards, work well with this; the server does not have to do much work.

• Cons: The downside is that the first time someone accesses the website, they might notice that it’s loading slower.

• Example: A social media feed that automatically shows new content without refreshing.

Server-side Rendering (SSR)

When using SSR, the server creates the entire page and sends it to be presented to the user. It’s similar to When your pizza is cooked and delivered, you can eat it right away.

• Pros: The benefits include quick loading on the first visit and good SEO, as search engines can see the whole page at a time.

• Cons: The server is involved more and there may be requests made to update the server.

• Example: A blog publication that should be placed high in Google search results.

Comparing CSR and SSR

How Next.JS Helps?

Next.JS let you pick the best rendering method.

• Page Router: For SSR, use getServerSideProps and for SSG (pre-rendering), use getStaticProps or in order to do CSR, use useEffect.

• App Router: By default, Server Components are used, but you can also use Client Side for providing interactivity.

• Hybrid Approach: With Hybrid Approach, use SSR for pages that focus on SEO and CSR for pages that are interactive.

When to use what?

• SSR or SSG: is recommended for blogs, online stores and pages that should rank well and load quickly.

• CSR: If there are many clicks and updates in the dashboard, use CSR.

Real-World Example:

Let’s consider a news website as an example

• Articles: For fast loading and better Google ranking, you can use SSR or SSG to create your articles.

• Comment: To load comments onto the page dynamically, you can use CSR with the userComments variable.

• User profile: Also you can use the CSR to change or edit your personal information.

Conclusion

Choosing between Client-side Rendering (CSR) and Server-side Rendering (SSR) depends on your project’s priorities, whether it's SEO, performance, or interactivity. With powerful frameworks like Next.JS, you can seamlessly switch or combine CSR, SSR, and even Static Site Generation (SSG) to get the best. Understanding where and how your content is rendered helps you build faster, more discoverable, and user-friendly web experiences.

Frequently Asked Questions

Q. Is CSR different from SSR?

A. CSR works by creating pages within the browser; SSR takes care of page creation on the server.

Q. When should I use CSR in Next.JS?

A. When you need to use dashboards or live chats.

Q. When should I use SSR in Next.JS?

A. When your pages are blogs, informative articles or static content, you need them to load fast and help with SEO.

Q. What does SSG mean in Next.JS?

A. SSG prepares all of the pages during the build so they load fast.

Q. Is it possible to combine CSR and SSR?

A. You can combine them in the same app using Next.JS.

Q. Does rendering play a role in SEO?

A. SSR and SSG let search engines understand your content; CSR may need some additional work to set up.

Q. What do we mean by Server and Client Components?

A. Server Components work on the server; Client Components (with "use client") add to the browser, using interactivity within the browser.