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Root vs www hostname mismatch: diagnose crawler routing after setup

A practical workflow for diagnosing root and www DNS, redirect, canonical, sitemap, HTTPS, and crawler-response mismatches.

Operations
Jul 2, 2026
4 min read

example.com and www.example.com are separate hostnames. They can use different DNS records, certificates, redirects, origins, and crawler response paths.

That is why a setup can appear correct on one URL and fail on the other.

Quick answer

If the server already sends complete HTML, you probably do not need Prerender Buddy. If visitors see a complete JavaScript page but bots receive thin HTML or an empty app shell, Prerender Buddy can help by serving rendered HTML to search engines and AI crawlers.

Common mismatch patterns

ResultLikely direction
www renders correctly; root returns app shellRoot bypasses the protected hostname or redirect
Root redirects to www, but every path lands on homepageRedirect does not preserve path/query
Root works; www fails HTTPSCertificate or validation record is incomplete for www
Browser works; crawler request differsUser-agent routing or proxy path differs
Search Console tests another versionProperty, sitemap, canonical, or internal links use the other hostname

Test both hostnames without assumptions

Terminal
1curl -I https://example.com/pricing
2curl -I https://www.example.com/pricing
3curl -I -A "Googlebot" https://example.com/pricing
4curl -I -A "Googlebot" https://www.example.com/pricing

Compare:

  • final URL after redirects
  • HTTP status
  • certificate validity
  • response headers
  • title, canonical, H1, and readable content
  • whether a matching request appears in render logs

Pick one canonical public hostname

If www is protected by Prerender Buddy, a common structure is:

Request flow
1example.com/pricing
2  -> 301 https://www.example.com/pricing

The canonical tag, sitemap URLs, internal links, Open Graph URL, and Search Console setup should support that same choice.

DNS and redirect checks

  1. Confirm which provider is authoritative for DNS.
  2. Check that the protected hostname points to the expected target.
  3. Remove conflicting A, AAAA, or CNAME records only for that hostname.
  4. Confirm the root redirect preserves path and query string.
  5. Wait for public DNS propagation before repeatedly resetting setup.
  6. Run Verify Installation against the final hostname.

Origin loop check

The separate origin must not be the protected public hostname. If Prerender Buddy receives www.example.com and forwards to www.example.com, requests can loop.

Use a builder, deployment, staging, or dedicated origin hostname that remains independently reachable.

Read the Root vs www guide, Origin URL guide, and DNS pending troubleshooting.

Who this is for

  • SaaS founders with already-shipped JavaScript websites
  • React, Vite, Vue, Lovable, Bolt, or Base44 users
  • SEO freelancers checking crawler-readable HTML
  • Agencies maintaining client sites without rebuilding them

You may not need Prerender Buddy if

  • Server HTML is already complete.
  • Static pages crawl correctly.
  • You are already rebuilding with SSR or static generation.
  • You only need an audit, not a rendering fix.

Final recap

Root vs www hostname mismatch comes down to what search engines and AI crawlers actually receive from your site.

Prerender Buddy does not guarantee rankings or AI citations. It helps with one specific technical problem: making sure crawlers receive readable rendered HTML instead of a thin JavaScript shell.

The first step is to check what bots see.

Check your website

Check what crawlers see to test whether the site sends readable HTML to search engines and AI crawlers.