Canonical tag checker
Check that every page tells search engines which URL is the real one — and that the answer actually works.
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Canonical tag checker: what’s checked
A canonical tag says “this is the version of the page to index”. It is how a site with tracking parameters, sorted listings or both www and non-www addresses avoids splitting its ranking signals across copies.
Canonicals fail quietly. A tag pointing at a URL that returns an error, or that isn’t a valid address at all, can drop a working page from the index; a canonical that points at another page’s canonical is treated as a weak hint. This checker reads the canonical on every crawled page and checks where it leads.
14 Crawling & indexing Pages have to be crawled and indexed before they can rank at all. These checks cover the files, canonicals and directives that tell search engines what they may fetch and keep.
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Broken canonical tag
A canonical tag pointing to a broken or wrong URL can deindex the page. Point it at the correct, reachable preferred URL.
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Canonical tags chained through another page
Google does not follow canonical tags from one page to the next -- a chained canonical is treated as a weak hint and it picks its own winner instead, so the consolidation you set up is forfeited. Point every canonical straight at the final URL.
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Missing canonical tag
A canonical tag tells search engines which URL is the “real” one when several are similar. Add <link rel="canonical"> to avoid duplicate-content dilution.
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Missing robots.txt
robots.txt tells crawlers what they may access. Add one (even an allow-all) and point it at your sitemap.
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Page blocked by robots.txt
Googlebot won’t crawl this page, so its content can’t rank — and a noindex on it is never seen. If the page should be found, remove or narrow the Disallow rule shown; if it’s meant to be private, stop linking to it and keep it out of the sitemap. Test the rule in Search Console’s robots.txt report.
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Page set to noindex
This page tells search engines not to index it, so it can’t rank. If that’s unintended, remove the noindex directive.
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Pages buried too deep
Pages many clicks from the homepage get crawled and ranked less. Flatten your structure and link to deep pages.
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SEO-unfriendly URLs
Long, parameter-heavy URLs are harder for users and search engines to parse. Use short, readable, keyword-relevant paths.
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Scripts or CSS blocked by robots.txt
Google renders pages with their CSS and JavaScript. Blocked files can make a page look broken or empty to it. Remove the Disallow rules that cover theme, plugin or asset folders; there’s no SEO reason to hide scripts and stylesheets.
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Sitemap URLs blocked by robots.txt
The sitemap asks Google to crawl URLs that robots.txt forbids, which Search Console reports as “Submitted URL blocked by robots.txt”. Either take those URLs out of the sitemap or stop blocking them.
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Soft 404 (server returns 200 for missing URLs)
Returning HTTP 200 for missing pages makes search engines index empty pages. Serve a real 404 status for URLs that don’t exist.
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robots.txt doesn’t name a sitemap
Add a line like “Sitemap: https://example.com/sitemap.xml” to robots.txt. Every crawler reads robots.txt first, so this is how Bing and others find your sitemap without a manual submission.
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robots.txt malformed
A malformed robots.txt can accidentally block your whole site. Validate it and confirm it isn’t disallowing important paths.
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www / apex not canonicalized
Serving both www and non-www without redirecting splits your ranking signals. Pick one and 301-redirect the other.
7 Content Search engines rank pages on the substance of the page. These checks look at how much unique, readable content each page carries and where it repeats itself.
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Duplicate H1 headings across pages
The H1 says what a page is about; when several pages say the same thing they compete for the same searches. Give each page a heading that describes its own content.
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Duplicate content
Identical content on multiple URLs splits ranking signals and can suppress all copies. Consolidate, rewrite, or add a canonical tag to the preferred version.
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Low reading-ease score
Hard-to-read text loses visitors. Shorten sentences and use plainer language to raise the reading-ease score.
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Low text-to-HTML ratio
A very low ratio of text to code can signal thin or template-heavy pages. Add meaningful content and trim unnecessary markup.
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Missing <h1>
The <h1> tells users and search engines the page’s main topic. Add exactly one clear <h1> per page.
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Multiple <h1> headings
Multiple <h1> headings dilute the page’s topic. Keep one <h1>; use <h2>/<h3> for sub-sections.
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Thin content (low word count)
Very thin pages give search engines little to rank. Add genuinely useful content, or consolidate thin pages into stronger ones.
How it works
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Enter your URL
Paste your homepage. No account, no install, no verification.
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We crawl your site
The crawler follows your internal links and runs every check against each page it reaches.
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Get your results
See your score and issue counts at once. A free account shows every finding, page by page, with how to fix it.
Frequently asked questions
Does every page need a canonical tag?
It is strongly recommended. A self-referencing canonical on each page costs nothing and removes the guesswork when the same page is reachable under more than one URL.
What is a canonical chain?
Page A names page B as canonical, and B names C. Google does not follow the chain; it treats the tag as a weak hint and may pick a different URL. Point every page straight at the final one.
Is canonical the same as a redirect?
No. A redirect sends people and crawlers to another URL; a canonical leaves the page reachable and only says which version to index. Use a 301 when the old URL should not exist any more.
Related free tools
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