The announcement from Yahoo!, Live & Google that they will be supporting a new "canonical url tag" to help webmasters and site owners eliminate self-created duplicate content in the index is, in my opinion, the biggest change to SEO best practices since the emergence of Sitemaps. It's rare that we cover search engine announcements or "news items" here on SEOmoz, as this blog is devoted more towards tactics than breaking headlines, but this certainly demands attention and requires quick education.
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To help new and experienced SEOs better understand this tag, I've created the following Q+A (please feel free to print, email & share with developers, webmasters and others who need to quickly ramp up on this issue):
How Does it Operate?
The tag is part of the HTML header on a web page, the same section you'd find the Title attribute and Meta Description tag. In fact, this tag isn't new, but like nofollow, simply uses a new rel parameter. For example:
This would tell Yahoo!, Live & Google that the page in question should be treated as though it were a copy of the URL moz.com/blog and that all of the link & content metrics the engines apply should technically flow back to that URL.
The Canonical URL tag attribute is similar in many ways to a 301 redirect from an SEO perspective. In essence, you're telling the engines that multiple pages should be considered as one (which a 301 does), without actually redirecting visitors to the new URL (often saving your dev staff considerable heartache). There are some differences, though:
- Whereas a 301 redirect re-points all traffic (bots and human visitors), the Canonical URL tag is just for engines, meaning you can still separately track visitors to the unique URL versions.
- A 301 is a much stronger signal that multiple pages have a single, canonical source. While the engines are certainly planning to support this new tag and trust the intent of site owners, there will be limitations. Content analysis and other algorithmic metrics will be applied to ensure that a site owner hasn't mistakenly or manipulatively applied the tag, and we certainly expect to see mistaken use of the tag, resulting in the engines maintaining those separate URLs in their indices (meaning site owners would experience the same problems noted below).
- 301s carry cross-domain functionality, meaning you can redirect a page at domain1.com to domain2.com and carry over those search engine metrics. This is NOT THE CASE with the Canonical URL tag, which operates exclusively on a single root domain (it will carry over across subfolders and subdomains).
Over time, I expect we'll see more differences, but since this tag is so new, it will be several months before SEOs have amassed good evidence about how this tag's application operates. Previous rollouts like nofollow, sitemaps and webmaster tools platforms have all had modifications in their implementation after launch, and there's no reason to doubt that this will, too.
How, When & Where Should SEOs Use This Tag?
In the past, many sites have encountered issues with multiple versions of the same content on different URLs. This creates three big problems:
- Search engines don't know which version(s) to include/exclude from their indices
- Search engines don't know whether to direct the link metrics (trust, authority, anchor text, link juice, etc.) to one page, or keep it separated between multiple versions
- Search engines don't know which version(s) to rank for query results
When this happens, site owners suffer rankings and traffic losses and engines suffer lowered relevancy. Thus, in order to fix these problems, we, as SEOs and webmasters, can start applying the new Canonical URL tag whenever any of the following scenarios arise:
While these examples above represent some common applications, there are certainly others, and in many cases, they'll be very unique to each site. Talk with your internal SEOs or SEO consultants to help determine whether, how & where to apply this tag.
What Information Have the Engines Provided About the Canonical URL Tag?
Quite a bit, actually. Check out a few important quotes from Google:
Is rel="canonical" a hint or a directive?
It's a hint that we honor strongly. We'll take your preference into account, in conjunction with other signals, when calculating the most relevant page to display in search results.
Can I use a relative path to specify the canonical, such as <link rel="canonical" href="product.php?item=swedish-fish" />?
Yes, relative paths are recognized as expected with the <link> tag. Also, if you include a <base> link in your document, relative paths will resolve according to the base URL.
Is it okay if the canonical is not an exact duplicate of the content?
We allow slight differences, e.g., in the sort order of a table of products. We also recognize that we may crawl the canonical and the duplicate pages at different points in time, so we may occasionally see different versions of your content. All of that is okay with us.
What if the rel="canonical" returns a 404?
We'll continue to index your content and use a heuristic to find a canonical, but we recommend that you specify existent URLs as canonicals.
What if the rel="canonical" hasn't yet been indexed?
Like all public content on the web, we strive to discover and crawl a designated canonical URL quickly. As soon as we index it, we'll immediately reconsider the rel="canonical" hint.
Can rel="canonical" be a redirect?
Yes, you can specify a URL that redirects as a canonical URL. Google will then process the redirect as usual and try to index it.
What if I have contradictory rel="canonical" designations?
Our algorithm is lenient: We can follow canonical chains, but we strongly recommend that you update links to point to a single canonical page to ensure optimal canonicalization results.
from Yahoo!:
• The URL paths in the <link> tag can be absolute or relative, though we recommend using absolute paths to avoid any chance of errors.
• A tag can only point to a canonical URL form within the same domain and not across domains. For example, a tag on https://test.example.com can point to a URL on https://www.example.com but not on https://yahoo.com or any other domain.
• The <link> tag will be treated similarly to a 301 redirect, in terms of transferring link references and other effects to the canonical form of the page.
• We will use the tag information as provided, but we’ll also use algorithmic mechanisms to avoid situations where we think the tag was not used as intended. For example, if the canonical form is non-existent, returns an error or a 404, or if the content on the source and target was substantially distinct and unique, the canonical link may be considered erroneous and deferred.
• The tag is transitive. That is, if URL A marks B as canonical, and B marks C as canonical, we’ll treat C as canonical for both A and B, though we will break infinite chains and other issues.
and from Live/MSN:
- This tag will be interpreted as a hint by Live Search, not as a command. We'll evaluate this in the context of all the other information we know about the website and try and make the best determination of the canonical URL. This will help us handle any potential implementation errors or abuse of this tag.
- You can use relative or absolute URLs in the “href” attribute of the link tag.
- The page and the URL in the “href” attribute must be on the same domain. For example, if the page is found on “https://mysite.com/default.aspx”, and the ”href” attribute in the link tag points to “https://mysite2.com”, the tag will be invalid and ignored.
- However, the “href” attribute can point to a different subdomain. For example, if the page is found on “https://mysite.com/default.aspx” and the “href” attribute in the link tag points to “https://www.mysite.com”, the tag will be considered valid.
- Live Search expects to implement support for this feature sometime in the near future.
What Questions Still Linger?
A few things remain somewhat murky around the Canonical URL tag's features and results. These include:
- The degree to which the tag will be trusted by the various engines - will it only work if the content is 100% duplicate 100% of the time? Is there some flexibility on the content differences? How much?
- Will this pass 100% of the link juice from a given page to another? More or less than a 301 redirect does now? Note that Google's official representative from the web spam team, Matt Cutts, said today that it passes link juice akin to a 301 redirect but also noted (when SEOmoz's own Gillian Muessig asked specifically) that "it loses no more juice than a 301," which suggests that there is some fractional loss when either of these are applied.
- The extent of the tag's application on non-English language versions of the engines. Will different levels of content/duplicate analysis and country/language-specific issues apply?
- Will the engines all treat this in precisely the same fashion? This seems unlikely, as they'd need to share content/link analysis algorithms to do that. Expect anecdotal (and possibly statistical) data in the future suggesting that there are disparities in interpretation between the engines.
- Yahoo! strongly recommends using absolute paths for this (and, although we've yet to implement it, SEOmoz does as well, based on potential pitfalls with relative URLs), but the other engines are more agnostic - we'll see what the standard recommendations become.
- Yahoo! also mentions the properties are transitive (which is great news for anyone who's had to do multiple URL re-architectures over time), but it's not clear if the other engines support this?
- Live/MSN appears to have not yet implemented support for the tag, so we'll see when they formally begin adoption.
- Are the engines OK with SEOs applying this for affiliate links to help re-route link juice? We'd heard at SMX East from a panel of engineers that using 301s for this was OK, so I'm assuming it is, but many SEOs are still skeptical as to whether the engines consider affiliate links as natural or not.
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If you have more questions, concerns or experiences to share about the new URL Canonicalization tag, please do so in the comments. I'll do my best to round up any unsolved queries and get some answers directly in the near future.
Further Reading on this topic from SELand, SEJournal, Yahoo!, Live & Google.
p.s. The search engines didn't consult with SEOmoz on this prior to release (I know, I know; dream on Rand), so Linkscape's index doesn't yet support the tag, but will beginning in the near future. We'll also try to provide some stats around adoption levels across the web as we're able.
Sorry, can I say that I don't see the fuss?
Yes, this makes life easier for SEOs. But there were a fair amount of ways of dealing with these sort of issues already. And what none of this will do (I don't think) is actually help people who don't attend industry shows or read search blogs. Which is most of the business population.
At the end of the day, I'd suggest that it's perhaps dangerous to rely on something like this (with all the uncertainty about how the various engines will treat it) and people should still aim to reduce the chances of duplicate content as much as possible.
This just strikes me as a bit of an industry stroke-fest*.
*Yes, I did substitute stroke for a different word.
But Ciaran, this is why you have a job - because you do attend industry shows and you do know what you're talking about. If all your clients knew what you do, then you wouldn't have any!
I agree that to a certain extent that this is a bit of a 'stroke-fest' but on the other hand it is a huge step forwards for many sites, particularly ecommerce sites that aren't using 301 redirects to remove their tracking codes and setting cookies, which in my experience is quite a few of them.
Again, I agree that people should structure their sites so as to avoid duplicate content as much as possible, but there are definitely occasions when canonical URLs are unavoidable, and any further options that we have as an industry to try and promote the correct URL is helpful to both us as SEOs and ultimately to searchers by having more relevant results.
True, and I don't disagree with that - possibly just the level of noise it's generating.
I've read this post three times now (excellent summary Rand btw) and checked out what the engines are saying.
While they may well be collaborating on the tag, it sounds like the approach has some serious inconsistencies already. I have to say as well, unless I'm missing something blindingly obvious, I think the importance is being somewhat over empasised.
My understanding is that this tag just tells a bot which is the most important version of a page, without the need to 301 every other version. Which is nice, but not exactly earth shattering.
Please correct me if I'm wrong but I haven't busted out the partty poppers just yet.
It will result in Wordpress plugins and CMS options that will probably make it simpler and more web-standard with the proles, or at least put it on their radar.
I'd agree with Ciaran. Why the fuss? :) yes, that's good news but we still have to see this in action. How much time will pass before we see a wealth of posts discussing if using canonical url tag is a red flag that the site has an SEO working on it because no one accept SEOs know about the thing? :)
I think the fuss assumes that this easy fix will eradicate many of the more 'industry secret' ways of taking care of the issue.
I know that right now it is an industry known change, but thats where everything starts. Robots.txt files, sitemaps, nofollows...they all started in the same fashion.
I agree that we'll want to see what time holds and how powerful this change truly is. I'd like to hope that it will be used by the engines as more than just a 'hint' but who knows.
I am agree with this.
I really don't think i coudl have said it better...
this is a good thing for shopping cart websites than can generate a different URL based on sort order in an ecommerce system..
however.. what makes you think the shopping cart can auto generate the correct URL...???
there are far better ways to pass link juice from old to new content than a 301.
and this just shows that all the 301 this , 301 this.. is not the best way to do things..
use an anchored refresh with spider timing and pass page rank from old to new without degradation.
I'm sorry, but absolutely everyone in the SEO community is missing the big picture here. The search engines have just given us the power to canonicalize any content, and here we are obsessed with duplicate content. If Google, Yahoo, and Microsoft all agree that something is canonical, who's going to argue? The mainstream media? The Pope? Here are just a few vastly more interesting uses:
1. Reshape Christianity: Before the early church decided on just 4 gospels, there were many so-called "gnostic" gospels. These were eventually ignored, due to politics, poor photocopier technology, and the fact that the Bible is already really, really long. Now, some of the alternative Gospels, like The Gospel of Thomas or The Gospel of That Guy Who Once Met Jesus At The Market And Was All Like Hey Jesus Can I Get Your Autograph can finally get their due.
2. Irritate Fan-boys: You remember when Jar-Jar's cousin Larry destroyed the Death Star instead of Luke in Timothy Zahn's 500th book? No? Well, now it's canon. Suck on that! Remember when Buffy and Willow made out behind the library on www.pervyfanfiction.com? That was hot. Consider it canonical!
3. Muppet Love Triangle: Remember when Miss Piggy, Gonzo, and Camilla the Chicken were all in the same room together on the Muppet Show? Man, you could cut the sexual tension with a boomerang fish. Of course, the conservative mainstream media considered their love taboo. Finally, it can be allowed to blossom.
These are just a few ideas, but I think you get my point.
good article thank you :)
Best comment I've seen in ages...
Not even remotely, but that doesn't mean I dont totally agree with you.
Good call, but they haven't all agreed anything (other than to use the tag). The inconsistency in implementation and policing of the tag is already looking dangerous - I'm not sure this is going to be the beautiful medly it appears to be on the surface.
But if it is I will erase this comment from the annals of history ;)
Only to canonicalize any content within the same domain, Pete.
You've officially crushed all of my dreams now ;) Nice to see you pop up over here.
I lurk in all sorts of places, but here quite regularly, Pete. :)
of course.. if the domain is the root entry of the record within google that would be where everything is attributed to
Cold shower and cold beer for Dr. Pete!
Dr. Pete,
Please correct me if I did miss your point. But you are saying "...canonicalize any content,..".
Canonical is just another way of saying "Search Engine Industry Standards". You know like HTML & CSS standards. Rules to play the game with.
This point you brought out is irrelevant. The only power they give us is the power of suggestion. Like always we are at the mercy of the search engines. All three (four if you actually count ASK), say they use it as a "suggestion". Some went as far as to say a "strong suggestion".
Also they, Google especially, have algorithmic devices in play which alert and account for abuse automatically. Also they only allow you to suggest for the domains you control. Which in my opinion is part of that abuse algorithm.
So honestly I have on idea what your getting at. If your point was that Miss Piggy and Gonzo are lovers your crazy. Everyone knows Miss Piggy has a huge canonical link to Kurmit all over her forehead. I don't care how big Gonzo's noes is, she has always loved Kurmit.
Great post Rand! Thank you for covering this new search engine offering so completely. For those of us that weren't at the conference yesterday, it is nice to be up to speed with such a quick read.
Matt's acknowledgment that 301 redirects (and now rel="canonical") do not pass full value is not a surprise to me. I've seen solid evidence of about 10% link value leakage with each 301 hop.
Though an important advancement, rel="canonical" is not a replacement for solid information and site architecture and well thought out URL conventions.
Totally agree, Lindsay, but it is a great way for many sites/clients to implement canonicalization that formerly would have required far more dev time and effort (and may never have been implemented). I think that's the biggest thing here - not that it's a substitute for building your websites with SEO in mind (which will still give a higher benefit), but that it can make a very common problem easier to bandage up.
Wow, I think this can be a great thing for ecommerce site that just don't have the ability to fix canonical product pages and where requesting 301s from the dev team takes weeks. Speaking as an in-house person, I can't wait to see how this develops!
In my mind this is not a huge deal, but a small valuable tool.
90% of people will never need it but the other 10% will absolutely love it.
Wow news of this must be spreading fast, my "I don't understand how google works" offline marketing collegues have just asked me if I'm excited about canonanosomething.
Unfortunately when I said yes and started to talk about it, assuming that they had read something I got blank looks and an accusation of being a geek, c'est la vie :)
Does the tag need to be added to the page that you want indexed (ex. www.seomoz.org/blog) or only the pages you want redirected?
The reason I ask is because if you have session ID's, obviously, you add it to the base page because the others are dynamic. So, what about redirects? Do you only have to add it to the base page?
I have an website hosted on dedicated server and google indexed its 8k pages with ip address urls. Now problem is that pages with domain name and ip address are indexed in google with duplicate content as usual. so how can i solve this problem so that only url with domain name will indexed in google.
* canonical url tag already added in website so i dont think url cannibalization help in this case
I definitely hope this works well with affiliate programs. I always insist links 301 redirect to prevent duplicate content, but the marketing department would prefer all links retain the affiliate tracking names. This almost sounds like it might be able to make every one happy.
Most of the Canonical examples pertains to individual pages. If a site is accessesible with or without the www. Would it be beneficial to add a link for the www. so that if www. were not used, search engines would not consider all pages accessed without the .www as duplicates? i.e. <link rel="canonical" href="https://www.yoursite.org/">.
what to do if having staging sites and get indexed by search engines? how to avoid the indexing of the staging sites?
Katha -
The best thing to do is to block the whole site from the the robots.txt file by having this:
User-agent: *Disallow: /
You can also put a NoIndex tag on each page: <meta name="robots" content="noindex" />
Thank YouWe have done changes as per your suggestion. Thank YouThanks a lot
Obviously the simplist use of this is to put it in your homepage and you take care of these issues:
www vs. non-www
/ vs. no slash
index.html vs. /
It still seems like those sort of issues are better fixed with redirects in the .htaccess file.
I mean, is it really that hard to configure Apache?
In a hosted environment like Volusion ecommerce, you are limited as to what you can do and the rel canonical tag is a good solution.
Interesting link, but it shouldn't be needed on well-designed sites. Having said that, there are various CMS that need to include this. Joomla, for example, is notorious for displaying the same page under multiple URLs.
I think that is too much. Why do we need to do extra work for search engines for them.
wow, awesome! what will happen stealing the content of other sites and point on them with canonical links.
You mean when scrapers take the whole page and you've got a canonical URL in the header that points to your site from their site?
Probably not much just now as it seems it's ignored if it points to a domain different to that on which it's served.
• A <link> tag can only point to a canonical URL form within the same domain and not across domains. For example, a tag on https://test.example.com can point to a URL on https://www.example.com but not on https://yahoo.com or any other domain.
The great thing about the canonical tag you can post the same content on multiple sites, designate which url you prefer to get all the credit, then place a canonicle tag with that url on each of those pages. Any link building or social shares to any of those pages will then credit that one url.
#1 I think it makes life a lot more easier
#2Here is the little paranoid blackhat in me screaming?
Is not this an easier way to identify the footprint of an ecommerce site for Google since the code on an ecommerce site is used on every page when used on a sitewide basis?Again this is just the paranoid in me. Great post Rand. Now let's go back to testing it.
I'd agree with Patrick Altofts post and Ciaran here - whilst its a new and usefull tool it doesnt seem to be a magic fix - seems to add to yet another one of the "standard things to get right". It'd be in the checklist of things to revamp or launch a site.
Maybe because there's not really been any big announcements from Search Engines for a while that this seems huge, yet in reality from concept to implementation its just not that huge.
Couple of questions:
If you add:
<link rel="canonical" href="https://www.seomoz.org" />
to your home page say.
Does that redirect link juice from deeper linked pages (i.e., someone linking to https://www.seomoz.org/blog)?
Put another way -
If you're suggesting to bots to use https://www.seomoz.org as a canonical url for all variations of https://www.seomoz.org, are you saying that link juice from all other sub urls should be sent to the canonical url?
If this practice is to be administered globally in the header, is there a risk of sending all your link juice to your home page, or perhaps hub pages that end with a trailing slash?
Gerard - no that shouldn't happen. If you put the canonical url tag on your blog and pointed back to your homepage, Google and the other engines basically say "you're an idiot, those two pages are completely different" and don't trust or use that canonicalization. If, on the other hand, they see it on home.html and home.htm and default.html all pointing to /, and those pages all have the same or very nearly the same content, they'll canonicalize the links back to the homepage.
Make sense?
This cleared up something I've been wondering about for a while. We have a homepage (/example-home) and thent the domain. Both are the same, and we are still not in the top 200 for the target term. But I had the cononical different for the /example-home homepage and the "just domain" homepage, and that might be our issue.
Let the monitoring begin.
Great post. Very informative.
I agree with Ciaran though and I'm not immediately convinced of any benefit over the alternatives eg, using robots.txt to 'block' crawlers from duplicate content - standard SEO practice with blogs, particularly with so many questions over its use. Maybe I've just not hit a situation where this tag would be useful.
Perhaps it is simply that robots.txt is a separate file and you can write this inline with the content - I prefer to "tag" content itself than keep a separate database.
Presumably the search engines will take a cursory glance at non-canonical pages to check they're the same as the "redirect" and then simply use that page address as an internal redirect (pointer in programming terms) in their db. That's going to save them an awful lot of disk space.
It's also going to reduce crawl time and processing needed, which may make the robots like your site better.
I got one of only 3 separate thumbs down so far on this thread .. what did I say? I'm curious to know. The only other down-thumbed comments were one guy who said "I don't get it, oh I do" and another who was a bit vehement.
Was I way off??
@Blue Snapper asked the benefit and I mentioned 1 perceived benefit (for me) on the client side and a couple of benefits on the SE side.
Perhaps SeoMoz could have a drop down that gave options for thumbs down "wrong, offensive, offtopic, ...".
These things happen...
Don't worry about it so much. And thanks for being part of the discussion. :)
it's just nice to know if you are wrong or just not liked!
maybe people are just cranky...
<blockquote>I'm not immediately convinced of any benefit over the alternatives eg, using robots.txt to 'block' crawlers from duplicate content - standard SEO practice with blogs, particularly with so many questions over its use. Maybe I've just not hit a situation where this tag would be useful.</blockquote>
Robots txt doesn't pass or preserve link juice. Any links to a page blocked by robots.txt or robots meta tags are lost juice. This acts more like a 301, but without affecting regular browsers.
Biggest use might be in tracking referrrer info and getting those affiliate or referrer tagged links to still count, without losing the URL parameter in a 301.
This is also a fix for the hundreds of companies using large-scale third-party CMS platforms that simply are not going to rebuild just for one customer.
That includes WordPress and Joomla too in most cases.
Joost De Valk didn't waste any time with a Wordpress plugin!
So much articles and discussion..but this is quite good .....
I don't get it. Well I think I do but to clarify.
By adding
<link rel="canonical" href="https://www.mydomain.com/subfolder">
in the header of any of these pages
www.mydomain.com/subfolder?parameter
www.mydomain.com/version/subfolder
These second set of pages are treated as duplicates of the canonical one?
That sounds right now I've read it back to myself. Don't know what I was confused about in the first place :)
Hi Stalker,
what about these two following pages?
www.mydomain.com/subfolder?parameter
www.mydomain.com/version/subfolder
This would be *so* much better if it could work across domains as well... Content syndication would become a lot easier.
If the tag sent pagerank across domains :-)
Could you imagine? Every WP hacker in the universe would have anothersuper nasty linkbuilding hack to do. Frightening.
Oh yeah, and a few white hat benefits too!
Well.... I'm far too whitehat to think of nasty uses. But I'm sure you could have it so it didn't necessarily pass PR, but at least made sure the original wasn't harmed by the duplicates.
You would never get more than %20 of original content producers to tag their content as original and eventually %100 of all content would get tagged. And I think I'm being optimistic with an %80 error rate.
Better to let the SEs try to figure it out from other factors.
You would never get more than %20 of original content producers to tag their content as original and eventually %100 of all content would get tagged. And I think I'm being optimistic with an %80 error rate.
Better to let the SEs try to figure it out from other factors.
Hi Rand,
any reference to Matt Cutts saying about the tag that "it loses no more juice than a 301"?
Indeed, 301'ing an URL not always transfers "everything", it's just that: think about one single URL of a thousands total belonging to a trusted domain: 301'ing it into a brand new domain will transfer link juice, but not domain trust/authority/age. You can bet it will not keep the rankings it used to have as long as it was in the old domain.
Anyway, I'm thankful to the big three engines for this new Canonical URL tag!
Know of any test results on this?
Would be interested too in seeing how a whole domain 301 passes juice,how long it takes to gain the same rankings - I always assumed it would be just a change in the URL that points to a particular db tuple in the Google/Yahoo/Live db.
There's a 'dampening factor' built into PageRank to prevent circular calculations and cyclic-linking traps. In the original papers, it was given an example value of 15%, meaning that of all the link-juice flowing into a page, only 85% of that overall juice could be passed on through that page's links, and 15% was damped out (some juice evaporated).
I've always found in practice that if you assume the same dampening factor will apply to a 301 as if it were a page with just one link, then your calculations will generally come out about right.
I think Rand just reported a conversation between a Mozzer and the Cutts guy...
I am still somewhat confused. I just checked the source code of my blog and saw that the plugin All In One SEO writes the <link rel="canonical" to all of my pages and posts. Based on what I am understanding, all of my content is being ignored by the search engines because this code makes them (search engines) interpret it to mean that all of my content is duplicated. Is this correct? If so, then it doesn't seem like it is good at all.
Fear not. What the plugin is doing is telling the SE's that those pages are the 'authoritive' version of the page, not to ignore it.
If you want to double-check, use the "site:" operator to see if those pages/posts are in fact indexed.
Providing you are using AIOSEO's default settings, you're fine.
As an aside, the "number of posts" setting on your blogs is common to most themes. If you change themes, simply use the same setting. Whenever possible, you don't want to change indexed pages/posts, since you will end up with a different URL. This will mean the previously indexed URL will come up 'page not found' until it is de-indexed, and your new page will be invisible until it is indexed. You would also lose whatever Pagerank, etc., that the earlier page had.
Btw, you're quite cute. Perhaps you'd be interested in some one-on-one 'coaching'... ;)
All-in-One Plugin in worpress is the best SEO plugin for wordpress. It contributes a lot to uplift the SEO optimization of your blog. Don't worry with that plugin. What is has right now is for better SEO optimization of your site..
Maybe, you have to work well in internal linking to index your post faster..
Michael is correct here, but you do need to be careful as some seo plugins will add rel canon. tag even if it is already there. It can end up quite messy.
Would this practice only be relevant within a dynamic site structure? Rand in the post you give ideas on when & where to use it...I'd also be interested in hearing a post on when not to use it or when it would actually be overkill.
some ouf you are saying its no big deal. just in my case we redesigned the site shrinking it effectively and there was no way to 301 nohtaccess no servcer side redirects, nothing was suported. all other avenues seemed risky so i lost good pages with page rank and then a month later after removal requests took effect we can use this tag ! oops good for situations like mine. although should realy have moved to a non windows server or something.
Rand posed the Q will it work in the future to handle affiliate links. when do these occure in the same domain? didnt get that:s its clear its a SE freindly way to do houskeeping on your sites index. It has to make the picture clearer to SE too. Spring clean there overloaded indexes as social booms
i was hoping it could focus variations like www. and /index.html simply to my .com but alas it cant
eggdaddy,
where you said. "i was hoping it could focus variations like www. and /index.html simply to my .com but alas it cant".
Why can't it?
So here's my question, who wants to be the first to test it out for redirecting linkjuice from a piece of linkbait?
The tricky thing with 301'ing linkbait over to a page that monetizes well is that users who click through via an external link don't end up seeing the linkbait when that's what they were expecting.
Now, would it be possible for somebody to continue showing the linkbait page to users, but telling the search engine "hey, count this page's linkjuice for page ____ instead"?
I know that you said that its effect would be limited to pages that have only "slight differences in content," but I bet we're going to see people testing out the limits on "slight" here.
Should be interesting!
What would you do in the case of category pages with multiple subpages?
Say you have:
www.example.com/category-1.html
www.example.com/category-1.html?p=2
www.example.com/category-1.html?p=3
Would you have a canonical url for each page?
<link rel="canonical" href="https://www.example.com/category-1.html" />
<link rel="canonical" href="https://www.example.com/category-1.html?p=2" />
<link rel="canonical" href="https://www.example.com/category-1.html?p=3" />
@RandFish,
Suppose, if the pages are as follow:
https://www.example.com/productname/ - Already set a 301 redirects to the page "https://www.example.com/productname/servicename.php" and the new page has been set as the canonical URL.
Now, following are the other pages under the the "/productname/", such as:
https://www.example.com/productname/who-can-use-productname.php
https://www.example.com/productname/Features-of-productname.php
Every page has a unique content. What I would like to know is that what canonical page would you suggest me for each of the above URL's?
I have a question though it may seem rather basic. I am now implimenting the tag on all of the url,s i manage. Some do have duplicate content. so would i put the tag on each page with the correct url deignation that should receive the link Juice.
Greeting,
Great post and certainly shed some light on my campaign.
Right now I have two 302 temporary redirect on my shopping cart and Go Daddy have told me I can not change it. So I have been looking for somewhere to put the rel=canonical tags, unfortunately there is only one HTML header editor for the entire site. So my campaign errors and notices is showing 68 rel=canonical notices and two 302 redirects. which is every product and category on my site. Is this a bad thing ??
If so will I have to use the HTML Header section to tag every page individually ? That seems to be quite the task and beyond my experience level. :/
Any advice would be greatly appreciated.
Michael,
S&M
Adult content site (NSFW)
I have a website https://www.backlinkandseo.com, this site having product pages for PR1, PR2.......PR6 Backlinks with same contents (Different in pricing). Google is not crawling my pages so do i need to use "canonical tag"?
Please revert ASAP.
Thanks
Lets say we have page A and page B. And we have set the canonical version to be page A.
Does pagerank and link juice passes from page B to page A?
Great article on the use of canonical tags!
My question is: would it be beneficial to have canonical tags on every page of a site given the following situation?
The site is on a CMS that servers the same content with and with out the file extension. i.e. site.com/product and site.com/product.aspx. Some pages have higher authority with the .aspx and others without.
I'd like to standardize on one or the other. Would it be better to use canonical tags or 301s? I'm thinking that 301s on the versions that I don't want may be better as in some cases a canonical would point to itself if they were on all pages.
Hi mozzers,
I would like to know if the canonical tag should have the trailing slash at the end?
I notice that SEOmoz uses this for the home page (with trailing slash):
and this for deep pages (without trailing slash):
What is the reason for doing it this way?
Thanks!
awesome. so very helpful. wondering if the SEOMoz folks have revisited the notion of canonical and have anything else to add on the subject as this post is a couple years old. thanks!
should i tag my homepage's /index.html page like so: <link rel=”canonical” href=”https://www.companyname.com” /> ? This would be the same as saying any links that point to /index.html, is really www.companyname.com , is that correct?
Yes, that's a good idea.
Hi,
I have different types of urls as below.
https://www.example.com/first/second/pages/prod.aspx?t=c
https://www.example.com/first/third/pages/prod.aspx?t=p
https://www.example.com/first/fourth/fifth/pages/prod.aspx?t=n
https://www.example.com/first/sixth/seventh/pages/prod.aspx?t=m
I have one master page for all this pages. How can I specify relative links for these type of urls?
<link href="/first/" />
Would the above canonical tag work for this type of requirement ?
Regards,
Dhaval
Amazingly, this is an important piece of the SEO puzzle that is almost always overlooked. This little gem DOES make a difference and takes only a minute to do. We have found this to be especially useful when taking on a new client that has previously had a helter-skelter link building process.
Suppose if your pages crawled coming back as a duplicate result. The difference is in the URL is one has www and the other does not. Is this a good time to use a canonical tag?
Hi all! I'm a little confused about using canonical tag's in my case. For example I have a page with these parameters
domain.com/paremeter1/parameter2/parameter3
parameter3 is slightly different variation of the page without this parameter (like color=blue for example). So, in my case I want to add a canonical tag for this page like:
domain.com/parameter1/parameter2
But, my question is, do I need a meta "noindex, follow" for page with extra parameter (3) as well or I don't?Thank you for your answers
Nice Article, but I don't understand why e.g. in the Code of this page there is a canonical to the very same page:
<link href="https://www.seomoz.org/blog/canonical-url-tag-the-most-important-advancement-in-seo-practices-since-sitemaps" />What sense does it make? Thanks
https://www.seomoz.org/blog/dispelling-a-persistent-rel-canonical-myth
Maybe that will help. Essentially, somebody could link to your page wrongly (e.g. without www). In these cases Google might add two pages to its index when there should really only be one. In most cases there wouldn't actually be a physically wrong url. Just somebody linking to the page wrongly.
I read about it in google thank you for nice description
hello,
Then what about those pages which are being redirected to other url?
ex:www.xyz.com/pages=1
www.xyz.com/pages=2
if i m redirecting these two using canonical url to www.xyz.com
then what about pages?
www.xyz.com/pages=1
www.xyz.com/pages=2
This is awesome news and an awesome Q&A review - credit Rand! I marvel if this notice has any kin to the Amazon cloaking affiliate links fiasco that occured at SMX Advanced?
We have recently introduced rel canonical into every page of our site (www.aferry.co.uk). So when people link to the site wrongly (e.g. without 'www') hopefully Google should only record one page on its index and not more. When we implemented the rel canonical we decided that case was important. So all the rel canonicals refer to a lower-case file name. However some files acutally have mixed case file names. E.g. https://www.example.com/Widgets.htm has: <link href="https://www.example.com/widgets.htm"/> Does this matter to Google? Will Google be reading all of these as two pages? Or does only the link matter? Thanks very much. Any help much appreciated or if you have seen a similar issue discussed elsewhere.
Great post. Kudos!
Excellent post as usuall. Removing a burden from web dev and solving multiple version issues. Thanks!
I agree really a great piece of information. I particularly like social network pages, it really helps alot for traffic and search engine rankings
we have to put canonical tag on every page of website or just on index page?
Informative discussion.. but i am still confused ..
i have a blog with pages like: www.clickperfect.in/seo-services.html, www.clickperfect.in/ppc-services.html Now what i want i want to copy these content to www.shamsherkhan.com/freelancer-seo, and www.shamsherkhan.com/freelancer-ppc SO after reading this post i just created this canonical code: <link rel="canonical" href="https://www.clickperfect.in/seo/services.html" /> i want to transfer all credit of my blog clickperfect to shamsherkhan.com site .. so confusion is that where to put this code. on clickperfect OR on shamsherkhan.com page. Where to put??? please Guide me
Can anybody help me?
I'm totally new and I already lost after reading this page.
I have over thousand pages related to one product (service) in over 1000 places/cities in many countries.
Do I should put ONE canonical URL to all this pages or just ignore this?
Regards,
Bogorge2
Hi Rand,
Hope your doing great!
I have a doubt that will Canonical URL Tag work for internal pages with Capital Letters to small letters of same domain. For Example: www.example.com/Seo-Moz,html to www.example.com/seo-moz.html.
I have a website with html version of URL structure such as www.example.com/Seo-Moz,html(Seo-Moz). Now i moved the website to Word Press and installed html extension plugin. Now the link seems to like www.example.com/seo-moz.html (seo-moz).with small letters in the sub page. As Word Press CMS is not taking capital letters in the URL
So, can i apply Canonical tag for the present page https://www.example.com/seo-moz.html as <link rel="canonical" href="https://www.example.com/seo-moz.html">. ?
For Old page www.example.com/Seo-Moz,html, it has some Page Authority of 30. But for the new page www.example.com/seo-moz.html has 0 page authority. While making Canonical tag, will it passes the link juice and authority from old page to new page?
Am sure that by doing 301 redirection will definitely passes all authority from old page to new page. But I have more than 60 pages of similar to above. If i do 301 redirection for all 60 pages, the site may be slow down. So am testing out with canonical tag for two to three pages of my website.
So, I request you to provide me some suggestions that will work out for my website.
Thanking You,
Hemanth Kumar.
SEO Specialist
im lost, do i add the conical tag to posts ? does the conical tag relate with posting duplicate articles on net from my site? https://www.solarpanelsforyourhome.us/
Hi Rand Fishkin,
Can we have more than 1 canonical URLs for a single page??
suppose I have 4 different URLs for a single page, for eg: www.homepage.com, https://www.homepage.com, www.homepage.com/index.html & https://www.homepage.com/index.html
Can I use the below code in the header to show that all the 3 URLs are canonical to www.homepage.com ??
<link rel="canonical" href="https://www.homepage.com" />
<link rel="canonical" href="www.homepage.com/index.html" />
<link rel="canonical" href="https://www.homepage.com/index.html" />
sir i am new in SEO and using canonical tag through yoast plugin. After uploading mys blog posts i put the url in canonical tag section. sir can you please tell me is it right way to do or is te really necessary for my website blog. my website is https://www.loanpoint.uk/blog/. I am waiting for your response sir.
<meta name='robots' content='noindex,follow' /><link rel="canonical" href="https://www.indiawebwide.com/" />
Please Suggest me is that correct Robots and Canonical?
Hi Hari! Just FYI, you may have a better chance of having your question answered in our Q&A forum. :)
very Nice Article by Mr.Rand its very helpful to me great!
if a webpage having More than one Canonical URL with two different webpage whats the action by web robots. will you pls explain it
Thanks
Hey good explaination there about canonical & 303 !
How to use canonical link for 2 domain ? but website have same content.
Hi Rand
thank you for your great work. We are currently running SEO services for a customer which has its website running on a Sharepoint platforms. Sharepoint includes a Search Engine Optimization feature which enable by default a canonical tag to page with URL with the following format - https://www.websitedomain.com:80/mypageurl.html. This format cannot be changed without disable the whole seo module.
I wonder why a canonical tag, which is mean to be used for duplicate contents handling by search engine should include a port reference. Do you have any experience on this? Is the port number in the url effecting the whole canonical tag?
Thank you
Hey Rand Fishkin,
If i use someone else blog content over my blog site and put "source=www.xyz.com" at the bottom of the blog, is it consider as a duplicate content ?
And if i use rel canonical tag in HTML for that is it ok or still it consider as a duplicate content ?
Thanks,
Kalpesh Makwana
It is considered duplicate content, and may also be a copyright violation -- you need to make sure you have permission from the source to republish their content.
Thank you for this nice information. Can We use Canonical tag for WP tags to avoid duplicate content?
A very clear explanation, thank you.
But, dDoes anybody know if in the canonical url it is necessary to use "&" or the html code for & (&)? Because tll now we have used in the canonical url the code & , but since for Google they were generated 17.000 errors now we are trying with "&", without using the html code. Does anybody know something more about this issue?
Here you find an example of the canonical url now:
<link rel="canonical" href="https://www.vernicispray.com/en/glow-in-the-dark-paints---high-performance/glow-in-the-dark-paints-photoluminescents-spray-and-brush/scheda_prodotto.jsp?id=2200&cat=134&subcat=163" >
<link rel="alternate" hreflang="en" href="https://www.vernicispray.com/scheda_prodotto.jsp?id=2200&cat=134&subcat=163&lang=en" >
<link rel="alternate" hreflang="it" href="https://www.vernicispray.com/scheda_prodotto.jsp?id=2200&cat=134&subcat=163&lang=it" >
<link rel="alternate" hreflang="fr" href="https://www.vernicispray.com/scheda_prodotto.jsp?id=2200&cat=134&subcat=163&lang=fr" >
<link rel="alternate" hreflang="es" href="https://www.vernicispray.com/scheda_prodotto.jsp?id=2200&cat=134&subcat=163&lang=es" >
Generally speaking, use "&" in the href="" attribute - you don't need to encode URLs (with "&") because this field is designated for a URL. Encoding the URLs could lead to a mismatch.
Great post. I have this issue with my blog showing 5 posts on one page and then when showing an individual post on it's own url it looks like duplicate content from the original window of 5 posts.
This should fix it.
I have a question about how to set the canonical url: if I have an article that is something like www.beer.com/freshbeer can I set the canonical to be like to link www.beer.com/freshbeer or do I have to set up a different link like www.beer.com/freshbeercanonical?
I am having the issue where, while I only have 1 home page, Google and SEOmoz is seeing 2 home pages. www.domain.com + www.domain.com/index.htm . Will canonical tags solve this problem? Also, which tag do I use?
<link rel="canonical" href="https://www.domain.com" />
or
<link rel="canonical" href="https://www.domain.com/index.htm" />
Usually with www. vs non-www. you don't need to set up canonical URLs. If you'd like you can tell Google which one to consider your homepage in Google Webmaster Tools.
I have a module like sitename.com/module/ and this is the index page of the module. (assume the module as products)
i have listed items with pagination of 5 per page
if the main index page has a title tag like 'once there lived a king' and other pages will have 'once there lived a king page 2' and so on.
in the main page i display the description about the site as a paragraph which is displayed in all others pages.
the url for the the pages are designed as sitename.com/module/ for the first page and sitename.com/module/page/2 and so on...
all the page will have unique listing. so it is the para at the top which is duplicated to all pages 1,2,3...
Do i need to canonical the pages to the main page that is sitename.com/module/ or will it be enough if i have the site description para only in the first page and not in other pages (/page/2, /page/3, etc)... so since the description is only on the main page other pages will not have it and all the listing are unique will this method be accepted as not duplicate and can i prevent using canonical links for this condition.
each listing in each /page/2/ etc will have links to the actual separate unique product description page
so which way should i go... your suggestion please...
if we use canonical URL tag in website which website can perform batter our original or that one which is using canonical tag ? if we use this tag can we get tanking for our another site ?
Fantastic informative article... thanks!
Hi,
I have 2 questions:
Question 1) If 2 of my below pages are offering same content and i want abc.html to be the primary page, on which page shall i put <link rel="canonical" href="" /> and what shall be the url in href so that search engine doesnt treat the other page i.e. xyz.html as duplicate content?
1) abc.html
2) xyz.html
Question 2) As there are multiple options for homepages like example.com, www.example.com, https://www.example.com, example.com/index.html so shall we put 301 permanent redirects to any one or put a <link rel="canonical" href="" /> on index.html?
Thanks,
SEObug
Hello Everyone,
Still 1 confusion in mind if website url www.example.com/sports/football/balls and i had put canonical tag to www.example.com/balls , So which url should i use for seo link building (SBM, Directory Submision, Forum, etc.) purpose and is it right canonical which i had insert .......?
Which way is the best way for a canonical tag if each of your websites only have one language version ex. Japaneese and the websites you have are not identical due to many loacal touches but somewhat similar. Should the canonical tags be placed to show the url as https://www.example.jp/ja-JP or https://www.example.jp?
Hello Rand! I tend to agree with you that the canonical URL tag attribute is similar to a 301 redirect in many ways. I believe that rel=canonical is very vital. If we really want to save ourselves from duplicate content issues then we need to have this rel=canonical turned on.
Very useful stuff with the example ,,,Thanks for your post.
Thanks Rand for such a nice post. All informative. This is awesome news and you explained the topic in very simple way. Pictorial representation sounds good. It will help a lot.
Just read it on the Google Webmaster blog. Awesome news!
What surprises me is that G Y and L are working collaboratively on this; why the sudden friendship?
They did the same on robots.txt if I remember
Ciaran and that robts txt file works really well doesn't it.. lol.
Fantastic post Rand. This should save plenty of time. Thanks
Do you think you can use this to fix the problem of comment pagination and duplicate content in wordpress?
When a posts' comments are split across several pages and URLs, the post at the top is the same on each URL but the comments are different. Although there is also a URL version - the /comment-page-1/ one - that is identical to the permalink.
Is rel = canonical the answer? Or is the content too different?
More here: www.malcolmcoles.co.uk/blog/use-rel-canonical-fix-duplicate-comment-problems-comment-pagination-in-wordpress/
I'm curious if this will work on an ecommerce site with pagination since the products on each of the paginated pages is technically "different" than the main category page...any thoughts?
Takes a bit of getting your head round but makes sense.
Cheers Rand
PS Rand, whilst your in the UK if you're up North let us know and i'll take you to the best real ale pub in Yorkshire.
I like that there is a new best practice technique to shout about..Woo Woo!
I have a dynamic lister page which when a user applies a filter then I want Google to consider that page to be a unique page.
Would applying this command strip back the URL to ...aspx/product_lister.aspx or could I have many canonical links to different depths of the lister page?
Also if I have inbound links to;
online.co.uk/product_lister.aspx?manID=25&utm_source=productfeed
would Google know that I had canonical link on my site to;
online.co.uk/product_lister.aspx?manID=25
And assign that inbound link to the URL without the utm_source
These are the things that I am still scratching my head at!
After scratching my head for a bit, it seems that it's a reactive tool rather than a proactive.
It seems that it is a cleanup exercise once you spot the duplication problem.
Do you think it would have made more sense if it worked the other way, you declare the links that are original page and all others should be stripped back and assigned to the original.
Am I barking up the wrong tree or does someone agree with me?
So would a good place to put these type of links would be page numbering or a sort by on a lister page?
Andrew,
Your not wrong or right. Its just a question of if the URLs are a problem. If they aren't then don't worry about it. If they are then give it a try if it works it works.
One thing I have learned about search engines, they always change.
I look at it more of a proactive thing. they can only do so much. More and more websites, especially with the wide use of AJAX technologies (yes FLASH is also an issue), are even using one URL for the entire website.
Point is they are and can only react to website creators and their fancy new techs (old techs too). because technology allows you to do almost anything you have to be adaptable, and do your best to create some sort of standards. The adapt ability is what I think gives Google their edge.
That is the idea Andrew. They know because you tell them in the <head> area </head>.
So long as those two pages have the same content on them you'll be right on.
damn safari 4 (delete please)
-
So, neither SEOmoz or SEMPO are usig this tag on their websites. I'm not seeing it on any of the 'big' SEO companies either. Hey Rand.....what's the current best practice??
This tag solves a lot of problems, but is still a band-aid at bestwhen it comes to internal link strength?!
For some CMS systems, this may be the only alternative.But if you've still got the resources to do it "right", there can be no substitute for clean internal links that all point to one single page, passing all link strength to that one single page.
The rel=canonical tag and the 301 redirect will never be able to fully repair the loss of internal link juice which stems from dup content problems.
Hi: As usual, the explanation is clear, detailed, illustrated effectively, timely. I'd heard about this but your post was so timely, it saved me visiting multiple sites to get the important information asap in a nutshell. Maybe the major search players will never share algorithims but at least they are starting to agree in principle which is fortunate. I've see a group of websites with duplicate content get no rank and the resolution is complicated. This should provide some standardization.
Hey...by the way...don't be discouraged that "they" did not consult you first before releasing this juicy tidbit...perhaps that would have been too democratic!
This is awesome news and an awesome Q&A coverage - thanks Rand!
I wonder if this announcement has any relation to the Amazon cloaking affiliate links fiasco that occured at SMX Advanced?
Why would you call what Amazon was doing a fiasco? I think it's pretty smart on their part - and I would do the same if I was managing my own program.
This is a nice addition, but I am still confused as to where you would even add the code in. I use Dreamweaver and as far as I am concerned I only have the one page. Somehow though the search engines have taken it as four pages like what Rand showed in his video. I just don't know how to access those pages to add in this tag.
You put the tag on the base page which in turn makes it show up on all 4 pages.
Do we know if this “new” tag has been recommended to the W3C or is it just adding to the bloat of proprietary markup that they keep churning out?
I think the collective feeling of a lot of Webmasters is that the relevancy of W3C standards, at least, as they apply to ROI from business activities on the web, is quite low. Being W3C compliant doesn't bring you anymore search traffic or visits or conversions, but using this tag properly very likely could (if you have problems you can't fix in other ways).
And to your point below - haven't you heard us consultants on the other side of the room complaining about how hard it is to get clients/sites to change htaccess or create 301s? For some companies, it's quite literally impossible to implement in any short term timeframe, while this is not.
On a slight tangent...
I think the collective feeling of developers is that sloppy code (due to the ignorance of W3C standards or laziness) leads to websites which are hard to manage, amend and crawl.
This can then lead to your second point; difficulties in implementing essential changes such as 301 redirects.
As such, in this situation I can't help but feel the canonical tag has value only in this context as a quick fix, rather than being a huge advancement.
If webmasters choose to ignore W3C that's their choice and they can fix that mistake using the canonical tag, but if they had (as has been pointed out) built their site properly they wouldn't need it.
Although we've already had ways of fighting duplicate content, I actually see this as a good practice to keep in mind when you start developing a new site. Build your new sites with the tag in place (where appropriate) and you might reduce future instances of implementing 301s and editing the robots.txt file.
Looks like a solid way to improve the signal to noise ratio ... for the signals anyway.
Good housekeeping tool (?) and possible method for improving link love from Google, etc long term (another wrinkle to keep SEO's on their toes?).
Any examples of pages already using the cannonical tag? I'd like to check it out.
Thanks
@joemescher - check this out
And yeah, I know I said this isn't the biggest deal ever but there's no harm in testing my theory... :-)
> How, When & Where Should SEOs Use This Tag?
The answer is much easier, Rand. The correct answer is: "When you or you developers are too lazy to fix the problems you have on your site!"
Adding a layer of cheap paint will not turn you old crappy car into a brand new one. It will loook better - but it will still be crap.
And an even bigger problem is if you are blind - which is the real issue with most developers. They are simply not aware of all the URL's that goes to the same content - and because they are not aware, they also don't know where to add this tag.
There are much better solutions available. Let me expplain to you my newest method next time we speak - the "catch all" method, that can solve 99% of all duplicate problems with a few lines of global code!
Hi Mikkel, Does your catch all method basically 301 any unrecognised url request to the root?
Mikkel,
I completely agree that there are better solutions. Why allow link juice leakage if you don't have to?
Hi Lindsay, You are write...!
It's kind of awesome - in that search engines are really listening to problems that a lot of websmaters have, and they're acting on it. Great!
Honestly I'm one of the SEO's that doesn't see what the fuss is about. In my mind, you can't beat a properly architected site with all the right rules and canonical redirects in place without relying on stuff like this. Maybe this just makes future SEO site design just that little bit sloppier.
Seems good, but me thinks this may be easily open to abuse then discounted like meta keywords.
I am thinking this could be quite helpful on scripts with lots of GET variables:
index.php?var1=var1&var2=var2
you could have:
<link rel="canonical" href="index.php" />
And it will prevent google from greating duplicate pages.
-Brenelz
I'm not an "SEO", but I started following this site to learn what I can do to improve my e-commerce site.
Honestly, I don't really get this whole thing. I must not understand it correctly.
My site has a ton of instances like what you've mentioned where different paramaters are called, but it is the same root page (maybe just page 2 of the products search results, or a color variation of a product, etc.). Google initially told me I had "duplicate content", but after a week or so, it became resolved within webmaster tools, and Google says my site is fine.
The sites worth anything that link to me always link to the root pages because it only makes sense. Maybe a few visitors might save a sub page to their bookmarks or something, but that seems to be it.
Clearly I'm missing something. Anyone interested in clarifying for a novice? :)
as i stated above..
you will need to generate a class within your website to figure out what search results page would be your standard url to use in canonicalization... then for each variance you will need to insert the rel=canon=blahblahblah stuff on each page where the content is the same but the url and the display are different.
you could attribute it to an sql query and parse the info on each page load with certain sections automatically having another field for the canonical content link...
if that is to complicated, show it to your programmer.
Excellent Post Rand, with great Explanation...
I think this tag will be useful in the case of duplicate content of pagination.....
Before I was placed Noindex tag in other pagination pages.... But due to this tag at least I can get link juice from other duplicate pages....(May be not 100% Link Juice)
Thanks for making this so clear, nice to see such a well writtern piece that covers all of the bases...
I think this is really nice. I'll admit that IA isn't my strong point but here's a quick example where I think this tag will be useful.
We currently have example.com/jobs
You can also go to example.com/jobs/city for one of the 8 cities we have offices in.
We also have example.com/city for all 8 cities.
Now we can put up example.com/city/jobs and canonically point it to the original jobs/city page.
Maybe there's a better solution from an IA standpoint but why do I have to worry about that when I have rel="canonical"!!!!
To make it more clear
example.com/jobs
example.com/jobs/seattle
example.com/seattle
example.com/seattle/jobs <- canonical pointing to example.com/jobs/seattle
I must say it is very informative.i had this trouble with couple of pages.It will be resolved now.Thanks Rand
Similar to eggdaddy's dilemma,
Have a client on windows server, can't move it, can't use .htaccess, can't redirect through server admin. I know, change host or change server... yaddah yaddah, not going to happen.
And to you "build the site properly from and SEO standpoint" evangelists...of course. And we did. Both internal and external links are monitored for compliance. But we are married to the host, period.
So we can use google's preferred domain and assign www version as preferred. Great. Google is set.
In Yahoo, not so much. So we have both www and non-www, and domain/index.html AND domain/ etc. in the index.
So dupe content for just about every page on the site. Seems as though this IS the only solution in this case. So it may not be a big deal to some sites, but to others, oh yes. Particularly windows servers with no admin control or ability to initiate it from the host.
So the $20 question: Will this fix the issue in Yahoo?
...sounds like it.
Will it adversely affect google results?
...shouldn't, but...
Is there some other way to do, better way?
not that I know of.
SE
im confused.. did you say that you cannot use rel="canonical" across 2 different domains?
Im asking because of this video by matt cutts seams to say otherwise. https://www.youtube.com/watch?v=x8XdFb6LGtM
unless i missed something.
thanks :)
Exactely the right article I was just looking for. Hope that the sessionID problem will be fixed with the canonical tag.
Hopefully Google will recognice it and the index will be cleander within the next days/weeks.
Thanks alot for sharing this.
Very nice article on this subject but I am still hanging.
I read about canonical domains and I understand but I do not know what to do here.
I am working on a website right now and these are the results I am getting.
"random search term" entered in Google returns:
first result: https://thiswebiste.com/newpage.aspx
second separate result: www.thiswebsite.com/oldpage.html
indented sub result www.thiswebsite.com
So the first result is the new page I created going for that keyword and it ranks #1. Also the first result is in https as we have a login on each page now so it is must be a secure page.
The second result is an old page that was never deleted and was indexed. It also shows up in other searches still and is an older page. If you click on it through good it will go to oldpage.html becuase it is still up. Also the root www.thiswebsite.com still shows up but if you click it resolves to the https://thiswebsite.com.
Multiple questions come up with this. If I go to the browser and type. www.thiswebsite.com it resolves to https://thiswebsite.com like it is programmed to.
The other question is I do not want to lose the www.thiswebsite.com and one page www.thiswebsite.com/oldpage.html ranks well. We are starting to rank on the https://thiswebsite.com pages I am creating and seoing for.
The owner of the website thinks its ok becuase we show up twice but I am not sure if it is hurting us in the long run. The new page and old page are differnet but the old has been around longer. The root www.thispage.com is older than https://thiswebsite.com. I have been SEO and getting links for https://thiswebite.com and some directories don't allow https://thiswebiste.com as a link.
I don't know what to do! Any suggestions?
I was thinking to 301 the www.thispage.com/oldpage.html to a https://thispage.com/newpage.aspx that is not identical but similar. My thoughts were to try to get rid of all of the www's but then we will lose those ranks. Maybe the real concern is we are showing up for both www and https in the ranks but our website grade is not excellent.
Is it acceptable to put the canonical tag in the header of the page the attribute is referring to for simplicities sake?So you can have the same header for all the pages, our programming dept is small and anything that can make his life easier and help our seo efforts is great.
According to Matt Cutts, yes it is.
From the recent interview with Eric Enge.
Matt Cutts: “It’s totally fine for a page to link to itself with rel=canonical, and it’s also totally fine, at least with Google, to have rel=canonical on every page on your site”
[Eric Enge's] Comment: Interesting way to protect your site from unintentionally creating dupe pages. Just be careful with how you implement something like this.
Does this apply for my page appearing over 3 urls like this;
1.https://example.com/
2.https://example.com/2010/05/17/blah-blah-blah/
3.https://example.com/category/blah/
And you would have the tags pointing back to number 2. ???! which is the main url for it?
Honestly, it depends on what the page content is. For example if the following had the same content:
https://yourdomain.com/example/
https://www.yourdomain.com/example/
https://www.yourdomain.co.uk/example/
https://yourdomain.co.uk/example
This is where you would use the canonical tag, choose one of the above you're happy with (the one that is indexed and set in webmaster central usually) then stick this in your <head>:
<link src="https://www.yourdomain.com/example/" />
OK now i have a tricky question
lets say I chose the root og the domain redirect and all works perfec any convination of url poin to https://www.domain.com/
the canonical tag on the home need to poin Exactly to the https://www.domain.com/ so is this option
<link rel="canonical" href="https://www.domain.com" />
Or this one?
<link rel="canonical" href="https://www.domain.com/" />
Always go with a trailing slash ;-)
Anyone is there who can help me?
Hello there!
If you have an SEO question, you should definitely check out our SEO Q&A service over at https://www.seomoz.org/qa. You need to be a PRO member, but it's a great way to get your SEO questions answered! I hope this helps.
Cheers,
Aaron
Hi Rand,
As I am too late I don't know will you answer me or not. But I have been facing a problem since last year.
After reading this article about canonical tag I think it could be solve. But first I want to let you know about the problem.
The problem is, when I am searching on google with "site:mydomainname.com", it is showing the site's all indexed pages as well as with some different type of pages started with the astaric (*) mark as "*.mydomainname.com" or "*.mydomainname.com/page1.html"
I thought it was happening for the duplicate content or the sub domain issue. But I can't control it.
I am not giving my web site url here as some people could think that I am trying to promote it.
If the tag can solve the problem then please suggest me where should I use the tag because I can't follow the page, started with astric in my web server.
Waiting for your valuable reply.
I think by redirecting yourdomain.com to www.yourdomain.com, you can fix this problem.
And also
www.yourdomain.html
yourdomain.html
www.yourdomain.htm
yourdomain.htm
www.yourdomain.com/index.asp
yourdomain.com/index.asp
all such things has to be 301 redirected to your www.yourdomain.com
Great post Rand!! I am late in it :) I have a question what will happen if you use Cannonical tag and 301 redirect on the same page, for example: If you put cannonical tag in index.html page which points you to root domain and you also place a 301 redirect on index.html? What will happen? Will search engines use the first option that they see or there could be some penalties in doing so..
I wanted to try and get an updated view on the whole relative URL canonical thing. As far as I understand relative is allowed, but absolute is recommended. Has there been any updated views released lately that speak to this point?
Thank you, thank you- this is the best article I have seen explaining canonical URLs.
I like the article and the way you present it. Really useful to me.
Would you consider it best practice to go ahead and use the tag on every page, especially if many of the pages are created dynamically?
<link rel="canonical" href="https://www.yoursite.com/Page.html">.
So, even if you're on Page.html, and not Page.html?V=1. The search engines still know you meant for it to be Page.html? Or does it hurt you to have a canonical link in the head tag, pointing to the exact same page you're on?
Otherwise you'll need an if statement for every variable that says if V <> "" then show the canonical link code.
Correct?
Hi Cody,
I have included it on all pages that are accessable by the search engines.
If the tag matched the page i still display it so the engines know its in the right place.
Check out the site i have recently implemented it on.
https://www.appliancesonline.co.uk
I am particularly pleased with the lister pages.
Hi Guys,
It has been 3 months since this post and SEOmoz is yet to implement the tag on the site, What is the hold up? :)
We went live this morning and I am looking forward to monitoring its success.
ok so its been about 2.5 months since this tag was released. Anyone seeing good results from it by now. we are considering using it on a site, but I am not sure if I trust this yet. Let me know if it caused problems or was a miracle for you if you have tried it!
Rand,
Totally agree with you on the fact that this is by far the best thing search engines have done since they got together and implemented the xml site maps standard.
I have a bank client who's index was littered with thousands of partner IDs, Omniture SiteCatalyst tracking codes, default folder URLs, www vs no www, http vs. https, and the list goes on. Yes the list can go on, I have another client for example who's website created an infinitive amount of sub domains. That was a 1st for me, I thought I had seen it all.
I use to have to disallow the tracking ID urls to be indexed, so that the clients PPC campaigns and Partner / affiliates wouldn't get credit for search engine traffic (seo work, my work). It just screws with conversion rates for everything when a tracking URL gets indexed & ranked.
This solution of using a disallow statement wouldn't always work for session IDs, in most cases I had to leave those alone until xml site maps came out... even then I hated disallowing session ID URLs from being indexed. Clients always took a hit initially. Then it made me look bad and that SEO was a crock.
But in some cases where session IDs actually created security holes or issues with revenue (memberships sites and the like) we could sometimes justify disallowing sessions IDs.
Then of course there is striping tracking codes from URLs for search engines. Or if you will 301 redirecting tracking and session IDs based on browser user agent. These URLs are typically found in hyperlinks on websites that the client has no control over. You just never know who is goign to link to where with what URL.
Plus lets say you did get rid of session IDs, you still have all the legacy links, that people have up on their websites linking to your client''s domain.
But with this this whole new link tag I won't even need to have these discussions any more. Because, tracking IDs, sessions IDs, etc. can still be used. Now its only an indexing problem where the solution just impacts the SE index.
Just wanted to add this question and answer to the page for people wondering if the cannonical tag can be used for specifying the page across multiple domains.
From Matt Cutts' blog:
https://www.mattcutts.com/blog/canonical-link-tag/
im confused.. did you say that you cannot use rel="canonical" across 2 different domains?
Im asking because of this video by matt cutts seams to say otherwise. https://www.youtube.com/watch?v=x8XdFb6LGtM
unless i missed something.
thanks :)
Great article!!! I'll definitely be using the code, I'm quite new to search engine optimisation so reading stuff like this is really interesting. Although I'd like to hear some more information about it's results.
Great article but still got a question if anyone can help would be great.
I work in real estate and we have 1000's of houses from around the world on our site. Every page/property has a canonicle tag dynamically inserted into it and in a lot of cases the canonical tag is exactly the same as the url of the page itself.
Our SEO company says this won't do any harm but I'm concerned it will (based on what Google say about following a chain).
Can anyone shed some light?
Hi MacMoo,
Provided that the canonical tag itself only contains the original URL, the one you want to show up in the index, with no anchor tags or query strings, it should be fine to have one on every page.
I'd suggest checking out Matt Cutts' explanation of the canonical tag as well.
Nice Information rand, i have a domain can i used that tag.can i used it on my home page. my url is www. abcxyz.com, want to add canonical tag
<link rel="canonical" href="https://www. abcxyz.com" />
can i use
thanks Mr Rand for this great article.
It is very useful.
I always print out your articles and read them.
I think the standard will be the union of all the sayings about this tag
-has the same effect of the 301 on SE
-transitive
-not cross domain
-the first declaration of the canonical statement will count
-relative url is allowed, absolute one is recommenced
-tag is transitive
-tag is a hint not a command
-comparison should be done by SE for the contents to take decision
I think the tolerance will be in
-the 404 problem
-not index yet problem
-how much both contents could not be identical?
I think there is no way to trick SE, by using this tag
Hey all, have a big question that would really make a difference to me:
currently have, per majestic seo, 2k links to the https://domain.com site and 1k links to the https://www.domain.com - I should (perhaps of course) be using a 301 redirect on the https://domain.com (giving all link juice to https://www.domain.com) right? Thanks to this tag for bringing up this point.
Cheers - clarification much appreciated.
Great, information from Yahoo, Google and MSN
but my question is, would it be affect in duplicate content, as well? if the tag showing <link rel="canonical" href="https://www.seomoz.org/blog/"> (with slash trailing) but in fact the actual URL shows without slash trailing (https://www.seomoz.org/blog)
Err... ooo... uhm... I need to read more about this subject. Ignore this...
[edit]I agree with the guy below me. Not immediately impressed by the big bandwagon and hugging trusted methods of good site structure and fixes. I'm not a dynamic website kind of guy.
Rand,
Well explianed with graphics :)
I'm sorry if I missed this if it was covered here but how is this different from the hash that Rand described in the Whiteboard Friday video? Is this is a better solution than using the hash?
thanks share these information ...
Wow...great in-depth explanation of the new tag.
I wonder how this will be used or even abused by the SEO industry now that "articles" can be posted in numerous places and include the new tag to point "juice" back to a chosen website. I hope this helps clean up a lot of duplicate content issues...I just wish there was a solid way to keep people from ripping off articles from a site and then getting ranked higher than the original source.
I think if i read it right they said it wouldnt work across domains, only within them.