Moz Q&A is closed.
After more than 13 years, and tens of thousands of questions, Moz Q&A closed on 12th December 2024. Whilst we’re not completely removing the content - many posts will still be possible to view - we have locked both new posts and new replies. More details here.
When is it recommended to use a self referencing rel "canonical"?
-
In what type of a situation is it the best type of practice to use a self referencing rel "canonical" tag?
Are there particular practices to be cautious of when using a self referencing rel "canonical" tag?
I see this practice used mainly with larger websites but I can't find any information that really explains when is a good time to make use of this practice for SEO purposes.
Appreciate all feedback.
Thank you in advance.
-
As others have said above, combating scrapers is a big reason, but you're relying on lazy scrapers not removing the tags.
Another reason is to prevent rogue content management systems from attaching unnecessary query strings to URLs, creating pages that can end up loading infinite times under different URLs. A canonical tag in the source file would mean that any number of duplicate pages point back to the original. The same reason goes for sites that have issues with redirecting www / non-www URLs to the correct version, or who deal with the same problem regarding secure / insecure URLs. In all these cases, the canonical tag is a bandaid, not a cure - it would be better to fix the underlying problem of the rogue CMS, incorrect redirection, etc. but the canonical tag (self-referencing) is there if you need it.
Google doesn't seem to have an issue with it, but if you're at all concerned about the other engines, use with care.
-
People do it to stop scarpers, but if your going to write screen scraper it would not be hard to remove canonical tags as well. so I don't think much of the idea.
Bing recommends that you do not use self ref canonicals tags. It could be that a self ref canonical tag may be followed as is alluded to by Bing, meaning that lose a bit of link juice thought the redirect.
-
You may want to just use it on every page.
One good argument for using a self-referencing rel=canonical on every page is to combat scrapers. If they grab the entire code, including the rel=canonical, they are essentially telling the bots that your page is the original, and they'll be much less likely to outrank you for your own content.
Larger sites tend to generate the rel=canonicals automatically for every page, and give you the option to customize it where necessary.
-
What do you mean?
Like on site.com/pagea.htm there is a canonical set to site.com/pagea.htm? No harm in that. You should have a canonical URL whenever you want only one specific version of a URL.
Got a burning SEO question?
Subscribe to Moz Pro to gain full access to Q&A, answer questions, and ask your own.
Browse Questions
Explore more categories
-
Moz Tools
Chat with the community about the Moz tools.
-
SEO Tactics
Discuss the SEO process with fellow marketers
-
Community
Discuss industry events, jobs, and news!
-
Digital Marketing
Chat about tactics outside of SEO
-
Research & Trends
Dive into research and trends in the search industry.
-
Support
Connect on product support and feature requests.
Related Questions
-
My "search visibility" went from 3% to 0% and I don't know why.
My search visibility on here went from 3.5% to 3.7% to 0% to 0.03% and now 0.05% in a matter of 1 month and I do not know why. I make changes every week to see if I can get higher on google results. I do well with one website which is for a medical office that has been open for years. This new one where the office has only been open a few months I am having trouble. We aren't getting calls like I am hoping we would. In fact the only one we did receive I believe is because we were closest to him in proximity on google maps. I am also having some trouble with the "Links" aspect of SEO. Everywhere I see to get linked it seems you have to pay. We are a medical office we aren't selling products so not many Blogs would want to talk about us. Any help that could assist me with getting a higher rank on google would be greatly appreciated. Also any help with getting the search visibility up would be great as well.
Intermediate & Advanced SEO | May 23, 2017, 2:33 PM | benjaminleemd1 -
Why is rel="canonical" pointing at a URL with parameters bad?
Context Our website has a large number of crawl issues stemming from duplicate page content (source: Moz). According to an SEO firm which recently audited our website, some amount of these crawl issues are due to URL parameter usage. They have recommended that we "make sure every page has a Rel Canonical tag that points to the non-parameter version of that URL…parameters should never appear in Canonical tags." Here's an example URL where we have parameters in our canonical tag... http://www.chasing-fireflies.com/costumes-dress-up/womens-costumes/ rel="canonical" href="http://www.chasing-fireflies.com/costumes-dress-up/womens-costumes/?pageSize=0&pageSizeBottom=0" /> Our website runs on IBM WebSphere v 7. Questions Why it is important that the rel canonical tag points to a non-parameter URL? What is the extent of the negative impact from having rel canonicals pointing to URLs including parameters? Any advice for correcting this? Thanks for any help!
Intermediate & Advanced SEO | Jan 22, 2016, 3:35 PM | Solid_Gold1 -
Dilemma about "images" folder in robots.txt
Hi, Hope you're doing well. I am sure, you guys must be aware that Google has updated their webmaster technical guidelines saying that users should allow access to their css files and java-scripts file if it's possible. Used to be that Google would render the web pages only text based. Now it claims that it can read the css and java-scripts. According to their own terms, not allowing access to the css files can result in sub-optimal rankings. "Disallowing crawling of Javascript or CSS files in your site’s robots.txt directly harms how well our algorithms render and index your content and can result in suboptimal rankings."http://googlewebmastercentral.blogspot.com/2014/10/updating-our-technical-webmaster.htmlWe have allowed access to our CSS files. and Google bot, is seeing our webapges more like a normal user would do. (tested it in GWT)Anyhow, this is my dilemma. I am sure lot of other users might be facing the same situation. Like any other e commerce companies/websites.. we have lot of images. Used to be that our css files were inside our images folder, so I have allowed access to that. Here's the robots.txt --> http://www.modbargains.com/robots.txtRight now we are blocking images folder, as it is very huge, very heavy, and some of the images are very high res. The reason we are blocking that is because we feel that Google bot might spend almost all of its time trying to crawl that "images" folder only, that it might not have enough time to crawl other important pages. Not to mention, a very heavy server load on Google's and ours. we do have good high quality original pictures. We feel that we are losing potential rankings since we are blocking images. I was thinking to allow ONLY google-image bot, access to it. But I still feel that google might spend lot of time doing that. **I was wondering if Google makes a decision saying, hey let me spend 10 minutes for google image bot, and let me spend 20 minutes for google-mobile bot etc.. or something like that.. , or does it have separate "time spending" allocations for all of it's bot types. I want to unblock the images folder, for now only the google image bot, but at the same time, I fear that it might drastically hamper indexing of our important pages, as I mentioned before, because of having tons & tons of images, and Google spending enough time already just to crawl that folder.**Any advice? recommendations? suggestions? technical guidance? Plan of action? Pretty sure I answered my own question, but I need a confirmation from an Expert, if I am right, saying that allow only Google image access to my images folder. Sincerely,Shaleen Shah
Intermediate & Advanced SEO | Jan 21, 2015, 6:34 AM | Modbargains1 -
Using Canonical URL to poin to an external page
I was wondering if I can use a canonical URL that points to a page residing on external site? So a page like:
Intermediate & Advanced SEO | Jun 9, 2014, 2:37 PM | llamb
www.site1.com/whatever.html will have a canonical link in its header to www.site2.com/whatever.html. Thanks.0 -
De-indexing product "quick view" pages
Hi there, The e-commerce website I am working on seems to index all of the "quick view" pages (which normally occur as iframes on the category page) as their own unique pages, creating thousands of duplicate pages / overly-dynamic URLs. Each indexed "quick view" page has the following URL structure: www.mydomain.com/catalog/includes/inc_productquickview.jsp?prodId=89514&catgId=cat140142&KeepThis=true&TB_iframe=true&height=475&width=700 where the only thing that changes is the product ID and category number. Would using "disallow" in Robots.txt be the best way to de-indexing all of these URLs? If so, could someone help me identify how to best structure this disallow statement? Would it be: Disallow: /catalog/includes/inc_productquickview.jsp?prodID=* Thanks for your help.
Intermediate & Advanced SEO | Oct 16, 2013, 11:56 PM | FPD_NYC0 -
Set up a rel canonical
I have a question. I was wondering, if it was possible to set up a rel canonical. When I can't access the non canonical pages? For example, my site as at www.site.com , but the non cannocail is at site.com is their any way to set thet up without actually edting it at site.com ? Thanks for your help
Intermediate & Advanced SEO | May 12, 2013, 8:47 PM | PeterRota0 -
What is the best way to optimize/setup a teaser "coming soon" page for a new product launch?
Within the context of a physical product launch what are some ideas around creating a /coming-soon page that "teases" the launch. Ideally I'd like to optimize a page around the product, but the client wants to try build consumer anticipation without giving too many details away. Any thoughts?
Intermediate & Advanced SEO | Apr 18, 2013, 2:14 PM | GSI0 -
Any penalty for having rel=canonical tags on every page?
For some reason every webpage of our website (www.nathosp.com) has a rel=canonical tag. I'm not sure why the previous SEO manager did this, but we don't have any duplicate content that would require a canonical tag. Should I remove these tags? And if so, what's the advantage - or disadvantage of leaving them in place? Thank you in advance for your help. -Josh Fulfer
Intermediate & Advanced SEO | Jan 30, 2016, 4:49 PM | mhans1