Duplicate content wrecks your SEO. Google can’t tell which version of a page you want ranked, so it picks one — or worse, ignores them all.
You lose traffic because the wrong page shows up, or none do. The real issue is most people don’t even know they have canonical problems until rankings drop.
What Is a Canonical Checker?
Canonical Checker is a free browser-based tool that scans a URL and reports what the rel=canonical tag points to — if it exists at all.
It shows you the declared canonical, HTTP status, and redirects in one snapshot. No login needed.
Why It Matters for SEO
If you have 10 versions of the same product page and no canonical, Google treats them as 10 separate pages. That splits backlinks, internal signals, and engagement metrics.
Most people miss that even small URL variations — like ?sort=price or /index.php vs / — count as duplicates. Google recrawls most sites every 3-7 days, so bad canonicals pile up fast.
Bad canonicals cause ranking drops. A study of 1,000 e-commerce sites found 68% had incorrect or missing canonical tags on category pages.
How to Use It
- Go to https://scrawl.tools/tools/canonical-checker (no login needed)
- Paste any live URL from your site
- Hit “Check” and read the result in seconds
It’s fast, no setup required. You can check 50+ URLs in under 10 minutes.
What the Results Tell You
The tool shows the HTTP status, final URL after redirects, and what the rel=canonical tag points to. If there’s a mismatch, it flags it red.
You’ll see if the canonical points to a 404, a different domain, or a redirected URL. That’s how you catch silent errors.
Here’s what actually happens: your CMS auto-generates a canonical, but if you moved the page or changed domains, it doesn’t update. The tag stays broken.
The tool also shows if the canonical is missing, self-referencing (good), or points to another version. That tells you if you’re consolidating link equity or leaking it.
Check a few key pages — homepage, top product, blog posts. If those are wrong, the rest likely are too.
3 Mistakes Most People Make
- Assuming self-referencing canonicals are set automatically
They’re not on all platforms. WordPress does it, but many custom sites don’t. You must check.
- Setting canonicals to non-existent pages
You think you’re pointing to /product, but /product returns 404. Now Google ignores the signal. Happens more than you think.
- Ignoring HTTPS vs HTTP conflicts
Your page is on HTTPS, but the canonical points to HTTP. That’s a cross-protocol mismatch. Google may not respect it.
Most people miss that canonicals break after migrations. You switch to HTTPS, but old tags still point to HTTP versions. Silent SEO bleed.
You can also spot when pagination pages (like /page/2) incorrectly point to the first page instead of self. That hides deep content.
For complex sites, pair this with the Redirect Chain Checker to catch redirect loops before canonicals.
And if you’re auditing a full site, run the Broken Link Checker after fixing tags — broken internal links amplify canonical errors.
Check your most important pages now
Don’t wait for traffic drops. Fixing one bad canonical can recover hundreds of visits.
Test your URLs today with the Canonical Checker — free, no login needed.