Although Google can parse JavaScript pages, it is better not to use JavaScript for critical website elements such as content, links, or redirects. Google’s Gary Illyes has just confirmed this on Twitter.
In a discussion on Twitter, Gary Illyes said that JavaScript redirects are not a good idea. He said that IP based server-side redirects were better to redirect visitors based on their location. You can check the server-side redirects on your website with the website audit tool in SEOprofiler.
Pre-render JavaScript pages
In general, it is much better if your server handle’s most of the work. If your website uses a lot of JavaScript, it is better to pre-render your pages. That’s what Google’s Aleksej Dix said on Google’s Webmaster Conference in Zurich.
Server rendering generates the full HTML for a page on the server in response to navigation. This avoids additional round-trips for data fetching and templating on the client, since it’s handled before the browser gets a response.
Rendering on the server makes it possible to avoid sending lots of JavaScript to the client, which helps achieve a fast Time to Interactive (TTI). With server rendering you’re just sending text and links to the user’s browser.
With server rendering, users are unlikely to be left waiting for CPU-bound JavaScript to process before they can use your site.
This is important if your want to get better rankings
If you have a JavaScript based website, you should use server side rendering if the website is public, and if the rankings of the website on search engines are important. You do not need SSR if the website is not public.
In short: If you want to get high rankings on Google, use server side rendering if you have a JavaScript based website.
How do web crawlers see your web pages?
Use the website audit tool in SEOprofiler to check if search engines can parse the content of your pages:
