URL Canonicalization Test
The URL Canonicalization Test confirms that every variant of your homepage URL — HTTP vs HTTPS, www vs non-www, trailing slash vs none, uppercase vs lowercase — eventually 301-redirects to the same single canonical URL. When variants resolve independently you end up with up to eight different versions of the same page, all competing for the same backlinks and ranking signals. Proper canonicalization consolidates that authority onto one URL and is one of the cheapest, highest-impact technical SEO fixes possible.
What This Tool Checks
- http://example.com -> https://example.com (forced HTTPS)
- http://www.example.com -> canonical version
- https://www.example.com -> canonical version (or vice versa)
- Trailing slash consistency (always present or always absent)
- Uppercase paths redirect to lowercase canonical
- IP-address access redirects (or returns 404)
- Default index file (/index.html, /index.php) redirects to bare folder
Why It Matters for SEO
Without canonicalization, Google sees up to eight versions of your homepage as separate URLs. Backlinks pointing to different variants split ranking power across all of them, and Google may even index multiple versions and treat the rest as duplicates. Forcing all variants to a single canonical URL via 301 redirects consolidates link equity, eliminates duplicate-content risk, and is a one-time deploy that benefits the site forever.
How to Fix It
Pick one canonical version (HTTPS plus your preferred www / non-www / slash convention). Add 301 redirects at the server or CDN level so every other variant lands on the canonical in a single hop. Update internal links to use the canonical version directly. Re-run this test until all variants resolve cleanly to the same URL.
How It Works
We make HEAD requests to each variant of your homepage URL, follow any redirect chain, and verify that all variants ultimately land on the same final URL with a 200 status. Variants that resolve independently or chain through more than one redirect are flagged with the exact fix needed.
Common Mistakes to Avoid
- HTTP not redirecting to HTTPS (mixed content + duplicate URL)
- Both www and non-www resolving with 200 status
- Trailing slash and no-trailing-slash both serving 200
- index.html accessible directly instead of redirecting to /
- Long redirect chains (HTTP -> HTTPS -> www -> trailing-slash)
Quick Checklist
- HTTP redirects to HTTPS in one hop
- Either www or non-www resolves; the other 301-redirects
- Trailing slash convention is consistent sitewide
- No more than one redirect hop per variant
- Internal links use the canonical version directly