Check the canonical tag of any webpage — verify self-referencing canonicals, detect missing tags, spot cross-domain canonicals and prevent duplicate content issues.
Fetches the live page source and reads the <link rel="canonical"> tag.
Paste the full URL of any live webpage — including https:// — and click Check Canonical. The tool fetches the page HTML source via a server-side proxy and parses the canonical link tag.
The result shows the exact canonical URL found, whether it self-references the current page, whether it points to a different URL (cross-domain or cross-page), or confirms no canonical tag exists.
A missing canonical on a page accessible via multiple URLs risks duplicate content. A canonical pointing to the wrong URL can suppress rankings. Fix issues in your CMS or SEO plugin, then re-run the check to confirm.
A canonical tag is an HTML link element in the <head> with rel="canonical" that tells search engines which URL is the preferred version of a page. It prevents duplicate content issues when the same content is accessible from multiple URLs.
A self-referencing canonical points from a page to itself — for example, https://example.com/page/ has a canonical of https://example.com/page/. This is best practice. It explicitly tells Google this is the definitive URL.
Without a canonical tag, Google must guess which URL to treat as canonical. It usually gets it right but may pick an unexpected variation — such as the HTTP version or a URL with tracking parameters. Adding an explicit canonical removes that guesswork.
Cross-domain canonicals are used when the same content is intentionally syndicated on multiple websites. The secondary sites add a canonical pointing to the original source URL, telling Google to credit the original for ranking signals.
Yes — a canonical pointing to the wrong URL effectively tells Google to suppress the current page. This can cause complete loss of rankings for the affected page. Always verify canonicals after CMS updates, migrations or plugin changes.
The tool uses a server-side WordPress proxy (no CORS issues) to fetch the raw HTML source of the URL you enter, then parses the link[rel="canonical"] element from the head. Because it reads the final delivered HTML, it catches dynamically injected canonicals from JavaScript and SEO plugins.
A 301 redirect sends users and bots from one URL to another — the old URL stops working. A canonical tag leaves both URLs accessible but signals which one should be indexed. Use 301s when you want the old URL to stop being accessible.
Current best practice is for each paginated page to be self-canonicalising unless the entire series consolidates to page 1. This checker verifies exactly what your pages are currently doing.
