Single Page App (SPA) – good or bad for SEO?

For many, single page applications (SPA) are the perfect way to build websites. They’re easy to use, deliver a sleek result, and are fast! But SPAs rely heavily on JavaScript, which makes SEO specialists raise their eyebrows. So, is having an SPA site bad for SEO? And how should you optimize an SPA site? Those are the two questions we’ll try to answer today!

This is a general article about SPA sites and SEO, where we go through the potential issues that can arise and how Google might react. The problems we describe below are not absolute – not all SPA sites face these challenges. Our goal is simply to highlight what you should watch out for if you’re considering building an SPA site.

SSR/Prerendering

SPA websites can be loaded in different ways: directly in the browser, via SSR (server-side rendering), or through prerendering.

Websites that load directly in the browser rely heavily on JavaScript, which is probably the least favorable option. The relationship between JavaScript and Google is complicated – Googlebot cannot always read JavaScript, and this can lead to important parts of your site being missed when it crawls.

The issue lies in loading times when the site is not rendered from the server. For visitors, the page may appear quickly, but Googlebot has to wait until the JavaScript executes before it can see additional links to follow and then continue crawling your site. Sometimes the JavaScript rendering even ends up in a separate indexing queue at Google, which means it can take longer for new content on your site to be discovered. Since rendering JavaScript is more resource-intensive (and therefore costly) for Google, it is often deferred to a later stage. This can also save time for Googlebot.

Googlebot is often set to spend only a limited amount of time on each site before moving on, so there is a risk that it simply won’t have time to crawl your entire site if too much of the content is only loaded via JavaScript.

By using server-side rendering (SSR), the site is rendered on the server before being sent to the browser. This makes it easier for Googlebot to crawl and index the site, even if it may take slightly longer to load compared to a SPA site loading as originally intended. However, the benefits of having a site that is easier to index outweigh the minor loss in speed.

SPAs Don’t Have Unique URLs

Single page application sites are built in a way that doesn’t provide unique URLs. Because of how the site is structured, the entire site exists on a single page. This is a very mobile-friendly way to present a website, but it’s difficult for Google to handle.

Since an SPA is essentially presented as one single page, it’s hard to nearly impossible to rank for multiple keywords because Google can only interpret it as one big page. Internal links that aren’t written in HTML become difficult for Google to follow and index.

Before launching an SPA site, you need to make sure you have unique URLs for every page on your site so that Googlebot can find and index them.

So, yes, it’s possible to optimize an SPA site, but it requires more work and careful monitoring to ensure that the site is indexed correctly.

For those who want to dig deeper into the subject, here are two links with more information about SPAs and SEO:

https://www.searchenginejournal.com/google-shares-seo-tips-for-single-page-apps/384100

https://www.dotcms.com/blog/post/single-page-applications-seo-how-to-get-it-right

Otherwise, your SEO work continues as normal: optimizing titles, meta descriptions, and creating great content!

Good luck!