A conversation we have several times a year. A client has a React application, their content is not ranking, and somebody has told them search engines run JavaScript now, so rendering strategy is no longer an SEO concern.
The first part is true. The conclusion does not follow from it.
Rendering is a queue, not a guarantee
Crawling HTML is cheap. Rendering JavaScript is expensive, so it happens on a separate and slower pass. Your content might be indexed days later than it otherwise would have been. Or partially. Or, if the render throws on a page nobody ever tested headless, not at all.
For a marketing site updated once a month, that lag may genuinely not matter. For property listings, job postings, or an e-commerce catalogue, it is the difference between existing in the results and not.
Beyond crawlers
Server-rendered HTML also means link previews resolve in WhatsApp and LinkedIn, the page shows something before JavaScript loads on a train, and a visitor running a script blocker sees content rather than an empty shell. None of those are SEO. All of them are traffic.
The practical position
Render on the server anything whose discovery matters: listings, articles, product and category pages. Client rendering is entirely appropriate behind authentication, where no crawler goes and the user has already committed to loading the application.
Modern frameworks make this a per-route decision rather than a whole-application one. Use that, and stop arguing about it as though it were a single choice for the entire codebase.
Written by the Prakmas team, Hyderabad and Union City.
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