Type a tool name, for example "keyword density" or "transcript".
Check if a URL has a canonical tag and whether it points to the correct preferred URL.
A canonical tag checker shows whether a web page declares a preferred URL and where that declaration lives. Enter a page address and this free tool reports the canonical URL it finds, whether the tag is self-referencing or points to a different page, the HTTP status, and the source of the tag. Site owners and SEOs use it to catch duplicate content problems early.
A canonical tag is a signal that tells search engines which URL is the preferred version of a page when the same or very similar content is reachable at more than one address. In HTML it is a link element with rel="canonical" placed in the head of the page, and its href holds the preferred URL.
Duplicate or near-duplicate URLs appear all the time. Tracking parameters, sorting filters, print versions, http and https variants, and www and non-www hosts can all serve identical content. Google's Search Central documentation describes rel=canonical as a hint, not a command, so search engines may still pick a different URL if other signals disagree.
The first is the HTML head, which is the most common location. The second is an HTTP Link header sent with the response, which is useful for files that have no HTML head, such as PDFs. This tool looks in both places and tells you which one it used.
A self-referencing canonical points to the page's own URL. It is a sensible default for unique pages because it protects against parameter variants. A cross-page canonical points to another URL and tells search engines to consolidate signals there. That is correct for a filtered or duplicate page, but a mistake on a page you want to rank.
You can check a canonical tag in a few seconds by entering one URL and reading the result panel below it.
The tool works on public pages. Addresses that are not reachable from the open internet, such as local or private network addresses, return an error instead of a result.
Say you run a store and a product is reachable at https://shop.example.com/boots?color=brown, a filtered variant of https://shop.example.com/boots. You enter the filtered URL and click Check Canonical Tag.
The tool returns Canonical Tag Found with the label Points to Different URL. Analysis Details show an HTTP Status of 200, a Canonical URL of https://shop.example.com/boots, and a Source of HTML link element. That is exactly what you want: the filtered variant tells search engines to credit the main product page.
Now you enter the main page, https://shop.example.com/boots. The result says Self-Referencing, because the canonical matches the checked URL (a trailing slash difference is ignored). If instead the main page returned a canonical pointing to the brown variant, you would have found a real problem: your best page is telling Google to prefer a filtered duplicate.
Each result type has a clear meaning and a clear next step. Use this table as a quick reference.
| Result | What it means | What to do |
|---|---|---|
| Found, Self-Referencing | The canonical matches the URL you checked. | Usually fine. Confirm the URL is the exact version you want indexed. |
| Found, Points to Different URL | The page defers to another address. | Correct for duplicates. Fix it if the page should rank on its own. |
| No Canonical Tag Found | No canonical in the HTML or headers. | Add a self-referencing canonical using the snippet the tool shows. |
A 200 status means the page loaded normally. A 404 or 500 means the tool may be reading an error page, so any canonical it shows is not trustworthy. Fix the status problem before judging the tag.
Source tells you whether the canonical came from the HTML link element or the HTTP Link header. If both exist, the tool reports the HTML value as the canonical and shows the header value separately under HTTP Header Link. When those two values differ, search engines receive conflicting signals, so make them match or remove one.
A good canonical is an absolute URL with the correct protocol, host, and path, and it returns a 200 status. A poor one is relative, points to a redirect, a 404 page, or a noindexed page, or uses the wrong host. Click the Canonical URL in the results and verify what loads.
Anyone who publishes pages at scale benefits from a quick canonical check, and these are the most common situations.
If you are building tags rather than checking them, the meta tag generator can output a canonical link along with your other head tags. For multilingual sites, pair your canonicals with correct annotations from the hreflang tags generator.
Most canonical errors come from a handful of repeat mistakes, and each one is easy to fix once you can see it.
Write the full address, including https:// and the host. A relative value such as /boots can be misread, and this checker will label it Points to Different URL because it does not equal the full address you entered.
Keep a single canonical declaration per page. Duplicate or conflicting tags, often added by both a theme and an SEO plugin, give search engines a reason to ignore both. If the result shows a value you did not expect, look for a second plugin or template adding its own tag.
The Self-Referencing label compares the canonical with the URL you typed. If you check http://example.com/page and the canonical says https://www.example.com/page, you will see Points to Different URL even though the page may redirect to that address. Check the final, preferred version of the URL to get a clean read.
A canonical should point to a live page with a 200 status. If it targets a redirecting or missing URL, update it to the final destination.
Your sitemap, internal links, and canonical should all name the same URL. Mixed signals weaken the hint. After fixing canonicals, review how the page looks in results with the Google SERP snippet preview and confirm the page structure with the HTML headings checker.
If you can see a canonical in your browser's inspector but the tool reports none, the tag may be added by JavaScript after the page loads. This checker reads the page as it is delivered, so a script-inserted canonical will not appear. Move the tag into the server-rendered HTML head so every crawler sees it.
The tool checks one URL at a time and reports what that single response contains, so it does not crawl your whole site or find every duplicate. It also cannot tell you which URL Google actually chose as canonical. For that, compare the result with the URL Inspection report in Google Search Console.
It reads the first canonical declaration it detects in the HTML, so a page with several competing tags may show only one. Pages that block automated requests, require a login, or fail to load may return an error or a non-200 status instead of a usable result. Finally, a correct tag is only a hint; search engines can still override it.
Knowing where a page's canonical points takes seconds and can prevent months of split ranking signals. Enter your URL in the checker above, review the status, source, and canonical URL, and add a self-referencing tag if none is found. For more tools that tidy up your head section and markup, browse the on-page SEO and meta tags tools.
Your report has been submitted. We will look into this issue.
A VPN changes your network exit. It does not guarantee anonymity.
Themes, plugins, code, video, audio, graphics & more from 90,000+ authors.
Web Development
Design & Media
Unlimited Access
Explore Envato Market