Bulk Canonical Tag Audit
Paste up to 500 URLs and the tool fetches each one, extracts the canonical tag, and surfaces the four classes of canonical bug: missing, self-referential (fine), cross-domain, and chain conflicts. Powered by a Cloudflare Worker.
Technical SEO Intelligence
Canonical bugs are silent: pages drop out of index with no error.
At enterprise scale, canonical tag drift happens through theme updates, platform changes, or copy-paste errors in CMS templates. The symptom is pages that stop appearing in search without any crawl error. This tool checks every URL in bulk and categorises the finding. All processing happens remotely on a free Cloudflare Worker: the URLs you check are not stored.
Input URLs
Next steps
Check the whole site, not one URL
SEORCE Technical Suite crawls every page and ranks technical issues by impact, so you fix what matters first.
Frequently asked questions
What does canonical do?
The
rel="canonical" link element declares the preferred URL for a page. Google uses it to consolidate duplicate or near-duplicate content under one URL.What canonical mistakes does this tool catch?
Missing canonicals, self-referencing missing, canonical pointing to a redirect, canonical pointing to a different domain, canonical mismatch with hreflang, canonical pointing to a noindex page.
Should every page have a canonical?
Yes. Even if it points to itself. Explicit self-canonicals prevent search engines guessing.
Can two URLs canonical to each other?
That would be a loop. Google picks one and ignores the loop, but it's a sign the setup is broken.
What is a canonical cluster?
Multiple URLs canonicalising to a single target. Common for pagination (page 2+ canonical to page 1) and filter variants. Modern practice: self-canonical each paginated page.
Can I use a canonical to merge duplicate products?
Yes. Point near-duplicate product URLs to one preferred URL. The ones with canonical don't get indexed but still accumulate referral signals.
Does Google always honour canonicals?
Not always. It's a hint, not a directive. If the signal set contradicts the canonical (different content, internal link patterns), Google may ignore it.
How do canonicals interact with 301 redirects?
301s are stronger than canonicals. Use 301 when the URL should disappear from the index. Canonical when both URLs should remain reachable.
Bulk auditing: how many URLs per run?
Up to 500 URLs per run via the Worker. For larger batches, split into runs.
What should a canonical look like?
<link rel="canonical" href="https://example.com/page/"> absolute URL, in the head, matching the live indexed URL exactly.Common cause of canonical bugs on e-commerce?
Faceted navigation generating URL variants (
?size=M&colour=red) that all self-canonical instead of canonicalising to the base category URL.Free · no account
SEORCE for Chrome, Edge and Firefox
Audits the page you are on: headings, meta tags, schema, indexability, and whether AI crawlers can read it. Export the result as a PDF. Free, with no account.
It audits one page at a time and does not track AI answers. About the extension
Across the whole site
One check here. Every page in SEORCE.
This tool does one job. SEORCE Technical Suite crawls your whole site with fast and secure crawlers and ranks technical issues by impact. AutoFix applies fixes for meta tags, schema, canonical tags, image alt text, headings and internal links for orphan pages on your live site, through one script tag, and the list keeps growing.
3,000+ users · Free forever plan, no card needed