Inspect Canonical

A lightweight and extremely easy Chrome extension that tells you the canonical source of any URL you are on. No more combing through the source code to understand if/when canonical tags point to a new destination. This extension does all the heavy lifting for you.

This extension will display one of three values. GREEN (self canonical) AMBER (Canonicalized) or RED (error)


Below are the conditions Inspect Canonical tests for, in the order it tests for them:

RED:
1. Page contains noindex robots meta
Message: "Page contains robots 'noindex' tag. Canonical tags are ignored. Click to view source"

2. No canonical in head but there is one elsewhere
Message: "Canonical tag exists but not in . Click to view source"

3. No canonical tag at all
Message: "Page has no canonical tag. Click to view source"

4. More than one canonical tag on page
Message: "Multiple ([X]) canonical tags found. Click to view source"

5. Canonical exists but is missing the href attribute
Message: "Canonical tag is missing 'href' attribute. Click to view source" - This is an unlikely case but still something I wanted to check for

AMBER:
6. Canonical present but differs to current URL
Message: "Canonical tag points to another URL. Click to visit URL: [URL]"

GREEN:
7. Canonical is present and correct
Message: "Canonical tag points to current URL. Click to view source"

So that's 7 hurdles to jump through to get a green status.