React has become one of the most popular JavaScript libraries for building user interfaces and web applications.
With its component-based architecture and virtual DOM diffing algorithm, React enables developers to build complex UIs that are fast, modular, and responsive.
However, React applications built using create-react-app, or other client-side-only frameworks have some drawbacks regarding SEO.
By default, React apps are rendered entirely on the client side, meaning the content is generated dynamically using JavaScript after the page loads. This presents challenges for search engine crawlers trying to index the content.
In this article, we’ll explore how server-side rendering and static site generation can help improve SEO for React applications. We’ll look at the specific problems with client-only React apps and then discuss how server-side and static rendering can solve those problems.
We’ll also walk through implementation details using popular React frameworks like Next.js and Gatsby.
Challenges of SEO with Client-Side Rendered React Apps
Single-page applications built with frontend JavaScript frameworks like React suffer from some SEO disadvantages compared to traditional server-rendered apps. Here are some of the main challenges:
- Content is not visible to search engine crawlers - Because content is rendered dynamically on the client side after the initial page load, crawlers cannot see the rendered content as they lack JavaScript capabilities. This means much of the app's content can be invisible to search engines.
- Crawl budget can be consumed rapidly - Modern search engine crawlers have limited ability to run JavaScript, but they impose a crawl budget to limit how much JS is processed to prevent overloading servers. If an app requires crawling many pages with heavy client-side JS, it can quickly use up the entire budget.
- Poor performance on mobile and slow connections - Client-side JavaScript takes longer to download and execute on mobile devices and slow connections before the content is viewable. This leads to poor user experience and performance.
- Low initial page loading speeds - The server can only return a mostly empty HTML shell for the initial visit, requiring the client to download and execute a lot of JS before useful content appears. This also hampers user experience.
- Not friendly for web sharing and bookmarks - When a user shares a link or bookmarks a page, only the initial empty HTML is captured, meaning no meaningful content is shared.
Clearly, relying entirely on client-side rendering limits SEO capabilities for React and other JavaScript apps. The good news is there are solutions to these problems.
Server-Side Rendering for React Apps
Server-side rendering (SSR) involves rendering your React app into HTML on the server before sending it to the client.
This means the initial page view will contain a fully rendered markup that search engines can crawl properly. SSR addresses the major SEO drawbacks of client-only apps:
- Search engines can crawl meaningful content - Since the React components are pre-rendered to HTML on the server, crawlers can see the full content on the initial visits.
- No crawl budget issues - No client-side JavaScript needs to be executed for the initial visit, so the crawl budget will not be consumed rapidly.
- Faster initial page loads - Pre-rendered HTML loads quickly without waiting for JS bundles and client-side rendering.
- Good performance on slow connections - The page is usable even before client JS fully loads since the server-rendered HTML contains the content.
- Link sharing works properly - Server-rendered HTML will contain actual content, so links shared on social media or bookmarks will work as expected.
SSR is critical for React apps that must be indexable and shareable by search engines and social media. The tradeoff is increased complexity on both the server and client side.
Implementing Server-Side Rendering
While server-side rendering is possible to implement manually, it's complex and requires expertise with servers and deployment. Luckily, React frameworks handle all the SSR complexity for you automatically.
The most popular framework for SSR React apps is Next.js from Vercel. Here's how it implements SSR:
- Components are rendered to static HTML on the server - A Node.js server runs the React rendering and component lifecycles to generate static HTML.
- HTML is returned for the initial request - The server returns the rendered HTML to the browser for the first-page visit.
- Client-side React takes over - After the initial server render, the client-side JSbundle boots up React to take over with dynamic functionality.
- Incremental static regeneration - Pages can be selectively re-rendered to HTML in the background and then served statically.
Next.js streamlines the process so you can focus on building React components and pages. Under the hood, it handles all the SSR complexity, like managing server build processes and routing.
Other frameworks like Razzle and After.js also implement SSR for React, but Next.js remains the most full-featured and widely used. For most applications needing SEO, Next.js is the best choice.
Static Site Generation for React Apps
Static site generation (SSG) takes SSR to the maximum level for performance and SEO. With SSG, the entire site is prebuilt into static HTML pages at build time instead of rendering on each request. The static files can then be served from a CDN.
SSG provides all the same SEO benefits of SSR, plus additional performance gains:
- No server-side rendering required - Pages are simple static files that can be served from a CDN without needing application servers.
- CDN handles caching and scaling - A content delivery network handles caching static assets close to users and horizontal scaling to absorb traffic spikes.
- Faster performance - Serving prebuilt files is faster than rendering on each request. No server computing is required.
- Easier scaling - Scaling is handled automatically by the CDN without scaling backend servers.
The tradeoff is that SSG only works for sites with mostly static content. For frequently changing dynamic data, SSR is preferable. SSG also requires a build/deploy step whenever the content is updated.
Implementing Static Site Generation
Like SSR, dedicated frameworks remove the complexity of implementing SSG yourself. Next.js and GatsbyJS both provide React frameworks optimized for SSG.
With Next.js, SSG is accomplished by:
- Exporting pages to static HTML at build time - Next.js generates static HTML for each page upfront instead of server-side rendering on each request.
- Rebuilding and redeploying when data changes - To update content, you rerun the build to regenerate a fresh static site.
- CDN serves the static files - Files are deployed to a CDN like Vercel or Netlify to be served globally.
- Falls back to SSR where needed - Next.js can selectively use SSR while the rest remain static for dynamic pages.
GatsbyJS is a React-based open-source framework that follows the JAMstack architecture for SSG:
- During the build, data is sourced from APIs, CMSs, databases, etc..
- Gatsby uses the data to render static pages from React components at build time.
- Pages are deployed to a CDN to be served as simple static files.
- Can preview builds before deploying and integrate with CMSs
SSG offers faster performance and better scaling for sites with mostly static content than traditional SSR. Both Next.js and Gatsby provide powerful ways to implement SSG with React.
Conclusion
React's client-side rendering approach delivers a fast, interactive user experience but hampers SEO reach and social sharing. Server-side rendering and static site generation unlock the SEO potential of React by pre-rendering sites to HTML.
Tools like Next.js make implementing SSR straightforward so you can focus on building your React app. For sites with mostly static content, SSG frameworks like Next.js and Gatsby enable blazing-fast performance by pre-building pages.
Compared to client-only React apps, SSR and SSG provide immense gains in SEO capability, page speed performance, and long-term scalability.
Any React developer who cares about SEO and performance should strongly consider utilizing these techniques for their next project. The ease of implementing SSR and SSG with frameworks means there's no reason not to.
If you want to become a programmer, then this article is your guide to becoming one. It explains everything from start to finish on how to build technical skills and what to do.
If you find this post exciting, find more exciting posts on Learnhub Blog; we write everything tech from Cloud computing to Frontend Dev, Cybersecurity, AI, and Blockchain.
Top comments (0)