Does ReactJS hurt SEO?

@RemiM If you say it's bad as a blanket statement, at least explain why you think it's bad.

@JussiMannisto Well, I don't think CSR is bad for SEO, IT IS BAD for SEO.

Why it can hurt SEO?

• Search engines struggle with JS rendering
• Empty initial HTML (bad for crawlers)
• Slower time to first byte & page load
• Metadata & Open Graph issues

But, don't take my words for granted, read what the leading name in the SEO industry has to say about it: https://moz.com/blog/audit-javascript-seo

@RemiM

Search engines struggle with JS rendering

They don't. JS pages need to be rendered separately, which takes more processing and has a bigger impact on the crawl budget. That may be meaningful for big sites with a lot of changing content, but it's meaningless for small sites.

Empty initial HTML (bad for crawlers)

Crawlers know about client-side rendering.

Slower time to first byte & page load

How could CSR cause a slower time to first byte? It could only be faster.

And what exactly do you mean by page load speed in this context? The page still has to be rendered somewhere, and hydrated on the client regardless. JS bundles have to be downloaded in both cases. All you're doing with SSR is offloading some computation to the server. That might help on slow devices, or allow crawlers to skip the separate rendering step, which is the real reason for SSR.

Metadata & Open Graph issues

You render all OG tags, structured data, and necessary meta tags server-side (in the blade template). SSR lets you do that in JS, which is convenient, but this is not an issue.

SSR isn't that hard to set up and you might as well do it if you have the capacity. But if you have a small site and your pages aren't broken, the actual SEO benefit from SSR is probably zero.

@JussiMannisto

They don't. JS pages need to be rendered separately, which takes more processing and has a bigger impact on the crawl budget. That may be meaningful for big sites with a lot of changing content, but it's meaningless for small sites.

Crawlers know about client-side rendering.

How could CSR cause a slower time to first byte? It could only be faster.

And what exactly do you mean by page load speed in this context?

While Google can index JavaScript-rendered content (see their documentation), it doesn’t guarantee they will, nor will the content perform to its full potential.

Would you like to leave it up to Google’s rendering engine to decide your “essential page content”? No, thank you.

When crawling a page, Google handles the initial HTML, crawling the links in the source code to discover new pages and then sending the page off for indexing.

However, when JavaScript is detected, the page requires additional processing to generate the rendered HTML. Once that’s ready, Google crawls from that page and prepares it for indexing.

These additional steps to render JavaScript content can slow down the crawling & indexing process and lead to issues like:

• Delayed rendering & indexing
• Incomplete indexing of content
• Rendering timeouts
• Missing or incomplete file downloads

It’s not difficult to see how issues like these could harm your SEO performance. This is especially true when websites rely on JavaScript to render critical links and content that your SEO performance depends on.

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SSR isn't that hard to set up and you might as well do it if you have the capacity. But if you have a small site and your pages aren't broken, the actual SEO benefit from SSR is probably zero.

You can have a small or local business where the SEO is critical—the size of the site does not matter for that topic.

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Now, it's easy to dismiss the previous article by the leading name in SEO mentioned, but everything is explained there, in details, and I'm curious about your input on this, as it was completely ignore in your previous answer for some reasons...

So while you may be correct in some aspect, the question was to know if ReactJS alone hurt SEO. Since this is a CSR library, the answer is YES, but of course there are solutions.