1.4 Rendering & JavaScript ✦CriticalVerified
Client-side routing with no SSR fallback
A single-page app that builds every route in the browser with no server-rendered fallback can serve crawlers a near-empty shell. Each route needs real HTML on first response.
What it is
SPA routes have no server-rendered equivalent.
Why it matters
Routes that only exist client-side can be hard to crawl and index reliably.
How to fix it
Provide SSR/prerendered routes with real URLs and proper status codes.
How to find it on your site
- Request a deep route with curl and check whether real content comes back or just an app shell.
- Test the route in URL Inspection and read the rendered result.
- Confirm each route returns its own server-rendered or pre-rendered HTML.
- Add SSR, static generation or prerendering for crawlable routes.
Cross-reference to ranking and citation factors
Routes that exist only after client-side rendering are slow and risky to index. Server-rendered routes are indexed reliably and quickly.
Impact
High for affected routes. Direct (documented SPA guidance).
Evidence
Use proper status codes and ensure SPA routes are crawlable/renderable. Google Search Central, Understand JavaScript SEO Basics