SEO Pulse Feature
Canonical tag checker
every scenario covered
Self-referencing, pointing elsewhere, missing, duplicated, or outside the <head> — see the canonical status of any page in one click, with SSR vs JS detection built in.
What it does
Canonical status,
one click away
The Canonical tile on the Overview tab shows the status of the current page's canonical tag at a glance — SELF, DIFF, or MISSING — colour-coded so you can see a problem before reading a single word.
Click through to the full canonical detail and SEO Pulse shows you the exact declared URL, whether it's self-referencing or points elsewhere, whether it sits inside the <head> element as required, and whether more than one canonical tag is present on the page.
Every canonical also gets an SSR or JS badge. If the canonical is only present after JavaScript runs — not in the raw server HTML — that's flagged immediately. A canonical that exists only in the rendered DOM may never be seen by a crawler doing a first-pass HTML-only fetch.
SELF
/products/running-shoes/
SSR
DIFF
/products/running-shoes?variant=blue
SSR
MISSING
No canonical tag found
MULTI
2 canonical tags declared
JS
Features
What's included
Overview tile at a glance
SELF, DIFF, or MISSING shown directly on the 12-tile Overview grid — colour-coded green, red, or orange — so you spot a problem before opening any tab.
Full declared URL shown
See the exact canonical URL as declared in the page, not just a status. Compare it directly against the current page URL to spot the discrepancy yourself.
Outside <head> detection
A canonical tag declared outside the <head> element is invalid per the specification and may be ignored by search engines. SEO Pulse checks placement, not just presence.
Multiple canonical detection
More than one canonical tag on a page creates ambiguity that search engines handle unpredictably. SEO Pulse flags this as a distinct issue from a single incorrect canonical.
Often missed
SSR vs JS badge
Shows whether the canonical tag is present in the raw server HTML or only appears after JavaScript renders the page. JS-rendered canonicals carry first-pass crawl risk.
Unique to SEO Pulse
Issues Tab integration
A canonical pointing to a different URL, missing entirely, or duplicated is automatically surfaced in the Issues Tab with a severity ranking and a plain-English fix suggestion.
Common scenarios
What each status actually means
Not every non-self-referencing canonical is wrong. Context matters — here's how to read each result.
✅ SELF — usually correct
The canonical points to the current page's own URL. This is the expected, healthy default for the vast majority of pages — it confirms this page is the preferred version of itself.
⚠️ DIFF — verify intent
The canonical points elsewhere. Sometimes correct (a print view, a tracking-parameter URL, a paginated page pointing to page 1) — but often a misconfiguration worth investigating, especially on a primary landing page.
❓ MISSING — check defaults
No canonical tag was found. Search engines will typically treat the page as self-canonical by default, but explicit declaration is recommended, especially on sites with URL parameters or duplicate content risk.
🔁 MULTIPLE — fix this
More than one canonical tag is almost never intentional. This commonly happens when a CMS or plugin adds its own canonical on top of a manually inserted one. Should be resolved to a single declaration.
FAQ
Common questions
What is a canonical tag? +
A canonical tag is an HTML element —
<link rel="canonical" href="..."> — that tells search engines which URL is the preferred, authoritative version of a page when duplicate or near-duplicate content exists at multiple URLs. It helps consolidate ranking signals to a single URL instead of splitting them across several near-identical pages.What does it mean if a canonical points to a different URL? +
It means the page is telling search engines that a different URL should be treated as the primary version, and this page itself shouldn't compete for ranking independently. This is sometimes intentional — for example, on a print-friendly page, a URL with tracking parameters, or a paginated archive pointing back to page one — but it's often a misconfiguration worth checking, particularly on a page you expect to rank on its own.
Why does it matter if a canonical tag is JS-rendered? +
Search engines don't always execute JavaScript on every crawl pass. If the canonical is injected by JavaScript after page load rather than present in the raw server HTML, crawlers on a first-pass HTML-only crawl may never see it — meaning the page could default to being treated as its own canonical, regardless of what was intended. SEO Pulse flags this with a JS badge so you know the canonical isn't guaranteed to be seen on every crawl pass.
What happens if there are multiple canonical tags? +
When more than one canonical tag is declared, search engines may ignore all of them or choose one unpredictably, since the specification assumes a single canonical per page. This usually happens by accident — for example, a CMS or SEO plugin automatically adding a canonical on top of one already added manually in the page template. SEO Pulse flags this as a distinct issue so it doesn't get missed.
Should every page have a canonical tag? +
It's widely recommended as a best practice, even on pages with no obvious duplicate. Explicit self-referencing canonicals remove ambiguity, particularly on sites with URL parameters, session IDs, or other variations that could otherwise create unintended duplicate content. SEO Pulse flags missing canonicals so you can decide whether to add one based on your specific setup.
Check canonical tags on any page instantly
Install SEO Pulse, open a page, check the Canonical tile. No setup.
★★★★★ on Chrome Web Store · 100+ users · No data sent to servers