Do URLs with canonical tags get indexed by Google?

[zasite]

Hi, we re-branded and launched a new website in February 2016. In June we saw a steep drop in the number of URLs indexed, and there have continued to be smaller dips since. We started an account with Moz and found several thousand high priority crawl errors for duplicate pages and have since fixed those with canonical tags. However, we are still seeing the number of URLs indexed drop.

Do URLs with canonical tags get indexed by Google? I can't seem to find a definitive answer on this. A good portion of our URLs have canonical tags because they are just events with different dates, but otherwise the content of the page is the same.

[zasite]

Thanks so much! Really helpful!

[MikeRoberts]

Not exactly. Its not so much that the canonical "supersedes" an index, follow tag.... a canonical tag establishes equivalency while a NoIndex is more like a "does not equal." The Index, Follow is still there and being seen by bots as they crawl... in fact, if you had NoIndex on a page with a Canonical Tag, it may not even see the canonical at all since you told it to NoIndex the page. The Meta Robots Index tag comes first allowing the bots to crawl and index the page but then the canonical sets up equivalency to a separate page. So if your canonical tag is being respected, it doesn't wind up doing the same thing as a NoIndex (though it may seem that way) nor does it do the same thing as a 301 (though there are similarities in how equity is passed). Since a canonical establishes an equivalency, you'll find that the Canon Page will eventually take the place of the Canonicalized Page in search results because you're telling them the Canonicalized Page _is _the Canon Page & that the Canon page is the right version of both.

[zasite]

Thanks, Mike! So, just to clarify, for a particular URL, if we have Meta Robots set to "Index/Follow" and that same URL has a canonical tag, the canonical tag would supersede the robot command and the URL would not be indexed?

[MikeRoberts]

If a URL was indexed and has since had a canonical added to it pointing to another page, it will eventually disappear from results. Basically the pages gets consolidated with its canon page. If the bots choose to respect the canonical tag in that instance, all signals get passed to the canon page while still allowing the page and information to be accessible by human visitors. As such, there's no reason to keep the page in the index because you're telling the bots that another page is the correct page instead. This is not the same as NoIndexing a page but will eventually remove a page from the index much in the same way that a 301 will pass equity along to another page while eventually removing the redirected page from the index in favor of the page being redirected to.