Understanding Server Side Rendering in Next.js: Benefits, Implementation, and Best Practices

Introduction

Next.js has quickly become one of the most popular frameworks for React development, thanks to its powerful rendering options. One of its standout features is server side rendering in Next.js, commonly referred to as SSR. This technique enhances SEO, improves initial load performance, and supports dynamic content fetching. In this article, we’ll explore everything you need to know about server side rendering in Next.js, including benefits, practical implementation, common use cases, and optimization techniques.

What is Server Side Rendering in Next.js?

Server side rendering (SSR) in Next.js refers to generating the HTML of a page on the server at request time. Unlike static site generation (SSG), which pre-renders pages at build time, SSR fetches data and compiles the page each time a request is made. This ensures that users always see up-to-date content, which is crucial for dynamic web applications.

Why Use Server Side Rendering in Next.js?

1. Improved SEO

Search engines prefer HTML content that is immediately available upon request. With server side rendering in Next.js, search engine crawlers receive a fully rendered page, enhancing the website’s search engine visibility. This is especially important for content-heavy or e-commerce websites.

2. Real-Time Data Fetching

For pages requiring up-to-the-minute data, such as stock prices, sports scores, or breaking news, server side rendering in Next.js ensures that the data is always fresh when a user visits the page.

3. Enhanced Performance for Initial Page Load

Since the HTML is already rendered on the server, the client receives a ready-to-display page, minimizing time to first contentful paint (FCP).

4. Personalization

With SSR in Next.js, it’s possible to customize pages per request, tailoring content based on cookies, user sessions, or geolocation. This is particularly useful for personalized dashboards or regional content.

Server Side Rendering vs. Static Site Generation (SSG) vs. Client Side Rendering (CSR)

Rendering MethodTimingUse CaseSEO BenefitsServer Side Rendering (SSR)At request timeDynamic pages needing fresh dataExcellentStatic Site Generation (SSG)At build timeStatic contentExcellentClient Side Rendering (CSR)On client-side after loadHighly interactive appsModerateHow to Implement Server Side Rendering in Next.js

Step 1: Create a Page Component

Any Next.js page can leverage server side rendering by exporting a function called getServerSideProps. This function runs on the server every time a request is made.

Example: pages/products/[id].js

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import React from 'react';

function ProductPage({ product }) {
    return (
        <div>
            <h1>{product.name}</h1>
            <p>{product.description}</p>
            <p>Price: ${product.price}</p>
        </div>
    );
}

export async function getServerSideProps(context) {
    const { id } = context.params;
    const response = await fetch(`https://api.example.com/products/${id}`);
    const product = await response.json();

    return {
        props: { product },
    };
}

export default ProductPage;

Best Practices for Server Side Rendering in Next.js

1. Minimize Unnecessary Server Calls

Only fetch critical data required for initial rendering. Avoid overfetching to improve response times.

2. Cache Responses

If the data doesn’t change frequently, consider caching responses at the server or using an edge caching layer (like Vercel or Cloudflare) to reduce server load.

3. Handle Errors Gracefully

Always handle API errors inside getServerSideProps. Return fallback data or redirect users to error pages when necessary.

4. Optimize Data Fetching

Leverage efficient backend APIs and reduce the number of requests within getServerSideProps.

Use Cases for Server Side Rendering in Next.js

1. E-commerce Product Pages

Product prices, stock availability, and promotions change frequently. SSR in Next.js ensures that users see up-to-date information at every request.

2. News Websites

For time-sensitive content such as breaking news, SSR ensures that users and search engines always receive the latest articles.

3. Personalized Dashboards

User-specific data, such as personalized recommendations or account balances, can be fetched and rendered server-side using user sessions.

Performance Considerations with Server Side Rendering in Next.js

1. Response Time

Since SSR generates HTML at request time, it introduces some latency compared to pre-rendered pages (SSG). Mitigate this with:

• Efficient API responses
• Edge caching for static segments

2. Server Load

For high-traffic websites, SSR pages may introduce scalability challenges. Load balancing and efficient caching can help manage this.

Combining Server Side Rendering with Other Next.js Features

Next.js offers flexible rendering strategies. For example:

• Use SSR for dynamic pages that require fresh data.
• Use SSG for static content like blog posts.
• Use Client Side Fetching for user-initiated actions after the initial load.

Example Hybrid Approach

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export async function getServerSideProps() {
    const data = await fetchDataForInitialLoad();
    return { props: { data } };
}

Then inside the component, you can fetch more data using:

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useEffect(() => {
    fetchAdditionalData();
}, []);

Common Mistakes When Using Server Side Rendering in Next.js

1. Over-fetching Data

Fetching unnecessary data increases response time. Be intentional about the data you load.

2. Ignoring Error Handling

If external APIs fail, users should see a helpful error page, not a blank screen.

3. Not Considering Caching

Adding caching layers can drastically improve performance for semi-dynamic data.

SEO Benefits of Server Side Rendering in Next.js

Since search engines receive a fully rendered HTML page, all content, including meta tags, structured data, and critical content, is immediately indexable. This provides a significant SEO boost compared to CSR, where crawlers might struggle to process dynamically injected content.

Conclusion

Server side rendering in Next.js is a powerful tool for building fast, SEO-friendly, and dynamic web applications. By understanding its strengths, limitations, and best practices, developers can create high-performance web pages that deliver an exceptional user experience. When combined with SSG and CSR, Next.js provides unmatched flexibility, allowing developers to choose the best rendering method for each page.