How to Check Canonical Tags on Many Websites at Once
Reading the canonical tag of one site is a view-source job; reading it for a whole prospect or client list is a job for a bulk tool. Each home page's link rel=canonical tag is compared with the page reached. The bulk canonical tag checker does that for up to 100 domains at once, or 500 after a free Google sign-in. Each row says the tag points to itself, points to another page or domain, has conflicting tags or is missing, and shows the URL it names.
A canonical is a hint to search engines, not an instruction, so a flagged row is a lead to look at, not proof of a fault.
What a canonical tag does
It is a link element in a page's head that names the preferred URL for the content, described in RFC 6596. When the same page is reachable at several addresses, search engines use it to decide which one to treat as the main one.
The by-hand way
- Open the site's home page and view the source.
- Search for
rel="canonical"and read the href. - Compare it with the address in the browser bar, including http or https and www or not.
- Note whether there is one tag, several, or none.
That is a minute per site, which is fine for five sites and slow for fifty.
Step 1: paste the domains
Paste one domain per line, or upload a CSV. Emails and full URLs work too, and the domain is taken from them.
Step 2: run the check
Each home page is requested once, five at a time. The tool reads the tag and compares it with the page reached.
Step 3: read the flagged rows
Points to another domain, a protocol that differs from the page, conflicting tags and no tag are flagged. Filter to those and download the CSV. To follow where a site's address actually ends up, use the bulk redirect checker.
What this check cannot do
- Only the home page's HTML is read.
- A canonical set by JavaScript or an HTTP Link header isn't seen.
- It is a signal read from the site, not a ranking result.
- Up to 100 domains a run without an account, 500 signed in.
For the broader job of confirming the sites on a list are even online first, see check if a list of websites is online.
Next: if the list also holds emails
The tool checks websites only. If the same list has contact emails, run them through the verify page: the first 100 checks are free with a Google sign-in, no card.
Try it now
Paste your domains into the bulk canonical tag checker.
Common questions
How do I check canonical tags on many websites?
Open each home page and read the link rel=canonical tag in the head. A bulk canonical tag checker does this for up to 100 domains at once, or 500 after a free Google sign-in.
Is a canonical that points elsewhere always wrong?
No. Sites use it on purpose to name a preferred domain or page. The row names the target so you can judge.
Does it check every page of a site?
No. Only the home page of each domain.
What if the canonical is added by JavaScript?
It isn't seen, because the page is read as plain HTML and no script runs.
Does a canonical tag guarantee which URL a search engine shows?
No. It is a hint, and a search engine can choose a different URL.
Check your list before you send
Real mailbox checks over SMTP, and nothing is sent to the address. Sign in with Google and your first 100 email checks are free, no card. Plans for bigger lists are on the pricing page.