Next.js: Server-side Rendering vs. Static Generation

As a web developer, the way you render your web pages significantly impacts your site's performance and user experience. With Next.js, a popular React framework, you have two main rendering options: Static Site Generation (SSG) and Server-Side Rendering (SSR).

Let's first understand what rendering means.

What does it mean to render a web page?

In simple terms, rendering a web page means creating and displaying the web page so that it appears on your computer or mobile screen for you to see and interact with seamlessly. It’s the process of taking all the code, content, images, and other elements of a website and turning them into what you see in your web browser.

Rendering is more like assembling a jigsaw puzzle or a Rubik’s cube. The web browser takes all the pieces (HTML, CSS, JavaScript, images, elements, and more) and puts them together to give you a complete display picture — the web page you’re looking at.

What is Static Site Generation (SSG)?

Static Site generation renders a page at build time. This means that for SSG, the process of creating the web page occurs before the site is launched and is accessed by users. Look at it this way: the HTML and content for each web page are pre-rendered or pre-generated, so they are ready and static (unchanging) when the website is deployed to a web server.

When a user visits a page on your site, the pre-rendered or pre-generated static HTML is delivered immediately to their browser, with no additional processing at the time of the user’s request.

What is Server-Side Rendering (SSR)?

Unlike static site generation, server-side rendering focuses on or renders a page in real-time. In this scenario, when you visit a website, the computer that hosts the website creates the page for you, like a chef preparing a dish as you order it at a restaurant.

SSR is great for web pages that need to show real-time information, updates, or content that frequently changes. In the same way, a restaurant can customize an order to your specific preference; that’s the same way a server-side rendered website prepares the page you want to visit as soon as you hit ‘Enter’.

Have you ever wondered why we use these techniques?

These two rendering methods boost the performance and user experience of your Next.js application. While SSG creates fast-loading, pre-generated pages, SSR ensures that the dynamic contents on your website are up-to-date and on track.

A significant reason why you should use SSR or SSG in your Next.js applications is the ability for your website to rank highly on search engines.

Now Let’s understand how Next.js works with Static Site Generation (SSG) and Server Side Rendering (SSR).

How Next.js Works With Static Site Generation (SSG)

To understand how Next.js works with static site generation, Think of it like baking cookies in advance. When you build your Next.js application, it creates static HTML pages just like baking a batch of cookies ahead of time.

So when a user visits your website, it's like handing them a freshly baked cookie that's already made, rather than starting from scratch each time someone wants one. This makes your Next.js application incredibly fast, as the pages are pre-made and ready to be served instantly.

Use Static Site Generation (SSG) when:

1. Content Doesn't Change Often: For pages that don't require frequent updates, like blogs, documentation, and marketing sites.
2. SEO Benefits: When you need good SEO performance since pages are pre-rendered and ready to be crawled by search engines.
3. Fast Load Times: When you want ultra-fast load times because pages are pre-generated and served directly to users.
4. Scalability: When you expect high traffic and want to ensure your site can handle it efficiently, as pre-generated pages reduce server load.

How Next.js Works With Server Side Rendering (SSR)

To understand the working SSR in Next.js, Imagine you're at a restaurant that cooks your meal only after you order it. When you request a dish, the chef prepares it fresh and serves it to you.

Similarly, with SSR, when a user requests a page, the server generates the HTML on-the-fly and sends it to the user's browser. This ensures the content is always up-to-date, making it ideal for dynamic sites like e-commerce stores or social media platforms where data changes frequently.

Use Server-Side Rendering (SSR) when:

1. Dynamic Content: For pages with content that changes frequently, such as e-commerce sites, social media platforms, or news websites.

2. Personalized Content: When you need to render content personalized for each user, such as dashboards or user-specific pages.

3. SEO and Initial Load Performance: When you need both good SEO and the fastest possible initial load time for dynamic content.

4. Data-Driven Pages: When your pages rely heavily on real-time data from APIs or databases and need to be up-to-date with every request.

Summary

This article highlights the key differences between Static Site Generation (SSGs) and Server-Side Rendering (SSR) in Next.js, providing insights into when, how, and why you should use either of these rendering methods.

However, the decision to use either SSG or SSR should be determined by your application’s specific requirements. SSG is preferable for faster page loads and minimal server-side processing, while SSR excels in scenarios that demand real-time updates, user authentication, and complex logic.

Your choice should depend on the nature of your content and the desired user experience for your website.