Canonical Tag Checker

Checks canonical link tags on a list of public URLs and flags missing, broken, or inconsistent canonicals. Returns a clean per-URL report ready for export.

What it does

SEOs and web developers often need to confirm, in bulk, that every important page carries a correct <link rel="canonical"> tag. This Actor fetches each URL you provide (following redirects up to a configurable limit), reads the resulting HTML, and reports whether a canonical tag exists, whether it is a well-formed absolute URL, and whether it points back to the page itself (self-referencing) or somewhere else.

Input

Field	Type	Description
urls	array of strings	Public page URLs to audit (max 200; URLs beyond the 200th are reported as errored rows, not silently dropped). Required.
maxRedirects	integer	Maximum HTTP redirects followed per URL before giving up. Default 5, range 0-10.
timeoutMs	integer	Total timeout in milliseconds for a URL, covering its whole redirect chain (the clock is not reset at each hop). Default 10000, range 1000-30000.

Example input:

{
  "urls": ["https://example.com/", "https://example.com/page1"],
  "maxRedirects": 5,
  "timeoutMs": 10000
}

Output

One dataset row per input URL:

Field	Description
url	Original URL provided as input.
finalUrl	URL after following redirects, or null on error.
statusCode	HTTP status code returned by the server, or null on error.
canonicalUrl	Value of the canonical link tag found in the HTML, or null if missing.
isMissing	true if no canonical tag was found on the page.
isSelfReferencing	true if the canonical tag points to the final URL itself.
isValid	true if the canonical value is a well-formed absolute URL.
error	Error message if the URL could not be fetched or was invalid; otherwise null.

For URLs that cannot be fetched (invalid format, timeout, too many redirects, network error, or beyond the 200-URL limit), the boolean/analysis fields are returned as null and error describes the failure.

Network access

This Actor only fetches the public HTTP(S) URLs you provide as input; it makes no other outbound calls.

Pricing

Pay per event: $0.004 per url checked. One URL fetched and its canonical tag fully validated (charged even when the canonical is correct).

You only pay for these events: the platform usage of the run is covered by the Actor. Failed fetches are not charged. You can cap the cost of a run with the maximum charge setting of your run.

Limits

• Up to 200 URLs per run.
• Public pages only — no login or authenticated content, no personal data collected.
• Redirects and timeout are bounded (0-10 redirects, 1-30 seconds) to keep runs predictable.

Use in your workflow

Replace <APIFY_TOKEN> with your token from Apify Console → Settings → API & Integrations.

HTTP API (curl) — run and get the results in one call:

curl -X POST "https://api.apify.com/v2/acts/devoted_laureate_r8f~canonical-tag-checker/run-sync-get-dataset-items" \
  -H "Authorization: Bearer <APIFY_TOKEN>" -H "Content-Type: application/json" \
  -d '{"urls": ["https://www.python.org/", "https://docs.python.org/3/"], "maxRedirects": 5, "timeoutMs": 10000}'

JavaScript (npm install apify-client):

import { ApifyClient } from 'apify-client';

const client = new ApifyClient({ token: process.env.APIFY_TOKEN });
const run = await client.actor('devoted_laureate_r8f/canonical-tag-checker').call({"urls": ["https://www.python.org/", "https://docs.python.org/3/"], "maxRedirects": 5, "timeoutMs": 10000});
const { items } = await client.dataset(run.defaultDatasetId).listItems();
console.log(items);

Python (pip install apify-client):

import os
from apify_client import ApifyClient

client = ApifyClient(os.environ["APIFY_TOKEN"])
run = client.actor("devoted_laureate_r8f/canonical-tag-checker").call(run_input={"urls": ["https://www.python.org/", "https://docs.python.org/3/"], "maxRedirects": 5, "timeoutMs": 10000})
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

AI agents (MCP) — expose only this Actor as a tool through the Apify MCP server:

{
  "mcpServers": {
    "canonical-tag-check": {
      "url": "https://mcp.apify.com?tools=devoted_laureate_r8f/canonical-tag-checker",
      "headers": {
        "Authorization": "Bearer <APIFY_TOKEN>"
      }
    }
  }
}

For agents: call it when you need to validate the rel=canonical tag of one or many URLs. Input: urls (list of URLs); optional maxRedirects, timeoutMs. Output: one record per URL: canonical URL, missing/relative/self-referencing flags, final URL after redirects, status code. Cost: $0.004 per url checked; failures are not charged.

FAQ

Can I check many URLs at once?

Yes, pass a list of URLs; you get one row per URL.

Am I charged for a correct canonical?

Yes, one event per URL checked; failed fetches are not charged.

Related tools

• Hreflang Checker - Validate hreflang Tags — hreflang alternates should be the canonical URLs
• Broken Link Checker - Find Dead Links on a Page — find links that point to dead pages