Google’s Martin Splitt, and Rachel Costello of Builtvisibile, discuss common questions about canonicalization in the latest episode of SEO Mythbusting.
Some of the busted myths include whether canonicalization is a signal or a directive, if it can be used as a redirect, site preference versus user preference, and more.
Here’s a quick recap of each question and answer, along with its corresponding time stamp in the video.
Canonicalization Myths Busted
Canonicalization is not a topical grouping (0:00)
Canonicalizing pages does not mean grouping together pages of a similar topic. Page content needs to be either identical or near-identical.
The most common canonicalization myths (1:29)
Top myths about canonicalization are that it’s a directive, and also that it can be used as a redirect. Further into the video they explain why neither myths are true.
Is canonicalization a directive or a signal for Google Search? (2:01)
A directive is an instruction that search engines automatically follow. Canonicalization is not a directive.
Rather, canonicalization is a signal. A signal is a hint for search engines which may or may not be used.
Splitt addresses this by saying:
“Putting a canonical tag on pages that are not the same is not going to work. Putting a canonical tag on each of the pages that are exactly the same is also not going to work.
It is a signal. It helps us identify what we want to canonicalize but it doesn’t say you have to use this.”
Should canonicalization be used as a redirect? (3:08)
Canonicalization is not a redirect.
Costello notes that canonical tags are sometimes used by site owners in an attempt by to group link equity wherever they can.
That’s not what canonical tags are designed for and they should not be used in that way.
Canonical tags are meant to be used when identical content is cross-posted to multiple places on the web.
The tag sends a signal to Google about which is the preferred page to be shown in search results.
What are the actual factors for duplication and deduplication? (4:25)
When it comes to deduplicating results in search Google uses content fingerprinting and a scoring system, in addition to using the canonical tag.
“Duplication and deduplication is actually done without much human interaction. We do content fingerprinting, we look at things like what is the gist of it really, what’s the information here, how does it relate to the site structure, what does it say in the sitemap.
So we’re looking at a bunch of different factors but they’re mostly technical factors.”
Google has created a scoring system based on all of the technical factors it looks at for deduplication.
The score is always being re-evaluated in the event that the content changes.
Site’s preference for the canonical URL vs user’s preference (7:33)
Google may override the site’s preferred canonical page with one that’s better for users.
This frequently happens with identical content in different languages.
For example – if there’s a canonical tag pointing to the English version of a page, but the searcher is located in Germany, then Google will show the German version of the page instead.
Canonicalization vs unique content on pages with a canonical tag (08:59)
Google may still accept a site’s preferred canonical page even if it has small amount of unique content that doesn’t exist on the other page(s).
However, if there’s so much unique content that Google doesn’t recognize the page as a duplicate, then the canonical tag is pointless.
For more details, see the full video below: