What JavaScript SEO means
It covers rendering strategy, hydration behaviour, routing, and how content and metadata are delivered. The core question is always the same: what exists in the HTML response versus what appears after scripts run.
Modern frameworks give you the tools to solve this — the failures are usually configuration choices rather than framework limitations.
Why it matters for AI search
AI crawlers raise the stakes considerably. Googlebot renders JavaScript reasonably well; several major AI crawlers don't render it at all.
That means a site can pass every Google-based test while being invisible to the platforms an increasing share of buyers use to research.
See it in action
The four failure modes, in the order we find them.
All five are configuration problems, not framework problems.
Every one has a native solution in React, Vue, Svelte and Angular ecosystems. They persist because nobody tested what a non-JavaScript fetch returns.
How to get it right
Diagnosing JavaScript SEO
- Fetch each template without JavaScript and compare against the browser version
- Check that title, meta description and canonical exist in the raw HTML, not injected later
- Use real anchor tags with href attributes for navigation, not click handlers
- Make sure content isn't gated behind tabs, accordions or scroll events that require interaction
- Test as multiple user agents, since capability varies enormously between them
Common questions
Is React bad for SEO?
No. React with server-side rendering or static generation is completely fine and often excellent.
React shipping a client-only bundle is the problem, and that's a configuration decision.
Do metadata tags need to be in the HTML?
For AI crawlers, yes. Titles, descriptions and canonicals injected by JavaScript are frequently missed.
Frameworks with SSR handle this natively — the metadata ships in the initial response.
What about infinite scroll?
Content loaded only on scroll is usually never seen by crawlers. Provide paginated URLs alongside the scroll experience.
The same applies to content hidden behind tabs that load on click.
Related concepts
These come up alongside JavaScript SEO constantly.