Canonical Tag Checker
Enter any URL to validate its canonical tag. Checks for self-referencing, protocol mismatches, trailing slash conflicts, og:url consistency, and noindex conflicts.
What This Tool Checks
Canonical tag presence
Verifies a canonical tag exists on the page
Self-referencing check
Confirms the canonical points to the page's own URL
Protocol mismatch
Catches HTTP canonical on HTTPS pages (and vice versa)
Trailing slash consistency
Detects mismatches between page URL and canonical URL
noindex conflict
Flags pages with both noindex and a canonical tag
og:url consistency
Compares canonical URL with Open Graph URL
Frequently Asked Questions
What is a canonical tag?
A canonical tag (rel='canonical') tells search engines which version of a page is the 'master' copy. When multiple URLs serve similar content (e.g., with and without trailing slashes, or with query parameters), the canonical tag prevents duplicate content issues by pointing all versions to one preferred URL.
Should every page have a canonical tag?
Yes. Every indexable page should have a self-referencing canonical tag — one that points to its own URL. This explicitly tells search engines 'this is the preferred version of this page.' Missing canonical tags leave duplicate content decisions up to Google's algorithms.
What happens if my canonical tag is wrong?
An incorrect canonical tag can tell Google to index the wrong version of a page (or not index it at all). Common problems: pointing to a 404 page, using HTTP instead of HTTPS, trailing slash mismatches, or accidentally canonicalizing all pages to the homepage. This tool checks for all of these.
Can I have both noindex and a canonical tag?
Having both noindex and a canonical tag sends conflicting signals. Noindex says 'don't index this page' while the canonical tag says 'this is the preferred version to index.' Google typically follows noindex, but the conflict can cause unpredictable behavior. Remove one or the other.
What's the difference between canonical and og:url?
The canonical tag (rel='canonical') tells search engines which URL to index. The og:url meta tag tells social platforms which URL to use when sharing. They should match — if they don't, social shares may use a different URL than what Google indexes, fragmenting your signals.
How do I fix canonical tag issues?
Ensure every page has a self-referencing canonical tag that matches the exact URL (same protocol, same trailing slash). If pages canonicalize to a different URL, verify that URL exists and is the correct preferred version. Fix protocol mismatches (HTTP vs HTTPS) and trailing slash inconsistencies.
Check canonicals across your entire site
CrawlRaven audits canonical tags on every page of your site — plus 200+ other technical SEO factors — in a single crawl.