Canonicalization: SEO Mythbusting

Key Takeaways

i think that a lot of people see canonicalization as kind of topical grouping which kind of isn't right at all they need to the pages need to be either identical or near near identical exactly yeah that's what it boils down to canonicalization is about duplication management so basically you want to remove duplications so that we don't have to crawl things multiple times and we don't have to like render and index things multiple times and we also do not serve them all the time like the same things basically in three different urls that's not good search results really right [Music] hello everybody and welcome to another episode of seo mythbusting with me today is rachel costello you are deep crawl technical seo and content manager so what is it that you're doing every day so i basically well i used to be a technical seo myself and now i've moved into more of the content production side of things so writing white papers articles to educate the wider dev community digital marketing community about technical seo and the impact it has awesome that's really interesting so you're seeing like a bunch of misconceptions and confusions and stuff and we picked an interesting topic didn't we we didn't what's the topic that you want to talk about today it's all about canonicalization all right so what are like the top myths and misconceptions that the community is dealing with so i think the first thing is that people think it is a directive you set a canonical tag it's going to be accepted um another one yeah exactly another one is that they kind of use it like a redirect so if you have a product page that goes out of stock you add a canonical back to the category page which doesn't really work that way because i've heard that the content needs to ideally be identical if not very similar so lots of things like that oh interesting all right let's let's start with the uh idea that it is a directive because it's not nope nope uh it is a signal for us right so when we talk about canonicalization we're talking about detecting content or the same content or very similar content that exists under different addresses and the different urls right so we can do many different things to basically identify these things right we can uh just crawl multiple pages and see like oh this is actually the same content we can also probably see if the same links and like the same kind of context is used but also we can use the canonical tag right it's a signal we're using many different signals to figure out if something is the same content or not and canonicalization with a canonical tag is just one of them so 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 like you have to use this that's that's a big one i think and you're right and you should not use it as a redirection either it's not a redirect i think people just want to group link equity wherever they can and it's maybe a bit of a desperate act to try and keep all of their link equity in one place it is it is again like canonicalization makes sense if you cross post the same content on different i don't know platforms or different channels in slightly different locations for whatever reason you're doing that that's where canonicalization comes in but if you are having something that goes out of stock you should either redirect it to something similar that makes sense for the user at that point or you can just tell us this is a 404 for the moment and might come back but do not just think that like you can no it's not the same as a redirection also you're wasting crawl budget that way because we're just not understanding like oh so you're saying this is the same as the other page but it clearly is not so we're just gonna continue doing this but if you have two pages that are identical and you're not canonicalization you're not canonicalizing them the way that it makes sense then we kind of have to look into both as well and sometimes you get these like flipping canonicals yeah what are the typical problems that you're seeing that people are having besides these misconceptions like what are people doing with them you think makes no sense so i think people are just not quite sure we've been trying to piece together um what these different signals are that play into effects you've got redirects site maps backlinks and things like that i think people are trying to weigh up how many of these signals they should add maybe they're kind of doing it like a maths equation like if i do these two things then this will mean that google picks my canonical tag that i want um but it would just be interesting i'm always interested to know more about how the signals are weighted which ones are more preferential to others because sometimes i see that maybe this is just my theory that maybe google puts more weighting to signals that are more likely to have been implemented by a human rather than maybe an auto-generated setting i don't know if that has any well um duplication and deduplication is actually done without much human interaction so this is all automated signals um but we do like content fingerprinting uh we look at things like what is what is the the gist of it really what are the there was the information here how does this relate to the site structure what does it say in the site map um so we're looking at a bunch of different factors but they're mostly technical factors okay yeah and we are basically scoring them on an ongoing basis so it's not that we're like determining it once and then just stick to it we are always looking at the fresh content that we got from crawl and then have a look at like does this this change if it changed is it now very close to what it has been before now maybe something that is has been in duplication is no longer a duplicate because it has changed its content so that's absolutely possible right but sometimes especially when pretty much everything is showing up in the same url structure and it's maybe like different language versions of the same thing but it is the same content then we might end up with a scoring that is very similar so we have both versions and let's say like one is 0.49 and one is 0.51 of what we think is a duplication of the other then it's really hard to pick which one will be the canonical and that can change right a change in i don't know how we crawl things or how the how the the crawler has fetched data and and and how it has been fetching the other pages beforehand might influence us to have like a tiny little bit of a jump in these two numbers and then the other one is the canonical so make sure that you're trying to give us as clear a signal as possible and not confuse the the algorithms uh that are working with figuring out which one is the duplication of which other thing because if we're having two um two equal pieces of content then how do we know which one we should pick exactly and you don't want google to be in that position where they feel like they have to pick for you or google what feels like it has to pick for you and it makes everything more complicated on your side as well especially if you're using things like search console right we are we're gathering data and showing you data based on the canonical so if it starts flapping between two urls then that's going to look really weird so anything else that you would say is unclear about it or is there something that makes your life really hard when it comes to canonicalization i think it's figuring out the certain thresholds you need to get to override google's decision on what is the preferred url because we can align all of our signals on site but i saw that john mueller on the ask google webmaster video about canonicalization he said that there's two aspects you've got um kind of the on-site signals but you've also got what you uh what google thinks that the user would most like to have a look at that is true yeah and that depends on a bunch of different things so for instance um we might canonicalize one language version over the other if if you were telling us that all of them are canonical at the same time and they have pretty much the same content especially if it's in the same language just for different countries um then we might show the version to the searcher that the searcher is in the country off so if we have a de version and an at version so the german version and the an austrian version that are pretty much the same they use the same currency they might have even the same price if you're unlucky we might show different urls to searches depending on where they are from right it makes more sense for a customer in uh austria to see the austrian version of the website rather than the german one even though the german one is the canonical so that might be a little confusing and misleading any other questions from your site yes so there was one question i had in that so if you if google accepts the canonical tag on a page that it will ignore any unique content on that page but then that's interesting because surely the pages have to be identical in the first place this is something i've heard that if there's any unique content on the canonicalized page it'll be ignored so how would that work would the canonical tag not be accepted then because they're slightly different pages so that depends on how different the unique content is if you have mostly the same content and then maybe have like one sentence that is slightly different then we might still think that it's pretty much the same thing and then we would not see the unique content necessarily if we think that it's just a copy of another page that is canonical if this page has the canonical then we will probably see the the unique content there as well because it's the page that we picked however if the content is completely different or different enough for the algorithms to decide that this is not a duplication then the canonical is pointless unless there's another page that happens or another url that happens to point to the exact same page then it becomes interesting again because then we have two different pointers do the same thing and we we get that often times that uh people are like linking two pages and accidentally have like some i don't know some url parameter that basically gets ignored uh or doesn't actually matter or there's like a slightly difference in the in the way that the url looks like um maybe you have like a slash d e something something and then like a slash to e uh something something question mark cash equals false or something like that that doesn't really matter then we might canonicalize to one of these pages and probably the one that does not have parameters and stuff but that also is debatable it might also happen that we kind of neglect something with parameters but that way you're again making it harder for us to pick the a canonical because if you're not saying like oh this is specifically the canonical we want and it's back to guesswork and i think that's the problem people are just trying to group pages topically maybe with canonicalization but that's not how it not how it works no thank you for confirming that canonical tags and canonicalization is about reducing duplication yes that's what it is for exactly awesome rachel thank you so much for being here and talking a little bit about canonicalization with me and i think that was useful and i hope you enjoyed it have a good time bye bye hey everyone i hope you liked the previous episode next episode me and glenn are gonna discuss site moves right site moves domain name changes url migrations and more so stay tuned and check it out