Block in robots.txt instead of using canonical?
-
When I use a canonical tag for pages that are variations of the same page, it basically means that I don't want Google to index this page. But at the same time, spiders will go ahead and crawl the page. Isn't this a waste of my crawl budget? Wouldn't it be better to just disallow the page in robots.txt and let Google focus on crawling the pages that I do want indexed?
In other words, why should I ever use rel=canonical as opposed to simply disallowing in robots.txt?
-
With this info, I would go with Robots.txt because, as you say, it outweighs any potential loss given the use of the pages and the absence of links.
Thanks
-
Thanks Robert.
The pages that I'm talking about disallowing do not have rank or links. They are sub-pages of a profile page. If anything, the main page will be linked to, not the sub-pages.
Maybe I should have explained that I'm talking about a large site - around 400K pages. More than 1,000 new pages are created per week. That's why I am concerned about managing crawl budget. The pages that I'm referring to are not linked to anywhere on the site. Sure, Google can potentially get to them if someone decides to link to them on their own site, but this is unlikely and certainly won't happen on a large scale. So I'm not really concerned about about losing pagerank on the main profile page if I disallow them. To be clear: we have many thousands of pages with content that we want to rank. The pages I'm talking about are not important in those terms.
So it's really a question of balance... if these pages (there are MANY of them) are included in the crawl (and in our sitemap), potentially it's a real waste of crawl budget. Doesn't this outweigh the minuscule, far-fetched potential loss?
I understand that Google designed rel=canonical for this scenario, but that does not mean that it's necessarily the best way to go considering the other options.
-
Thanks Takeshi.
Maybe I should have explained that I'm talking about a large site - around 400K pages. More than 1,000 new pages are created per week. That's why I am concerned about managing crawl budget. The pages that I'm referring to are not linked to anywhere on the site. Sure, Google can potentially get to them if someone decides to link to them on their own site, but this is unlikely (since it's a sub-page of the main profile page, which is where people would naturally link to) and certainly won't happen on a large scale. So I'm not really concerned about about link-juice evaporation. According to AJ Kohn here, it's not enough to see in Webmaster Tools that Google has indexed all pages on our site. There is also the issue of how often pages are being crawled, which is what we are trying to optimize for.
So it's really a question of balance... if these pages (there are MANY of them) are included in the crawl (and in our sitemap), potentially it's a real waste of crawl budget. Doesn't this outweigh the minuscule, far-fetched potential loss?
Would love to hear your thoughts...
-
I would go with the canonicals. If there are any links going to these duplicate pages, that will prevent any "link juice evaporation" from links which Google can see but can't crawl due to robots.txt. Best to let Google just crawl the page and see the canonical so that it understands that it is a duplicate page.
Having canonicals on all your pages is good practice anyway, as it can prevent inadvertent duplicate content from things like query parameters.
Crawl budget can be of some concern if you're talking about a massive number of pages, but start by first taking a look at Google Webmaster Tools and seeing how many of your pages are being crawled vs the total number of pages on your site. As long as this ration isn't small, you should be good. You can also get more crawl budget by building up your domain authority by building links.
-
I don't disagree at all and I think AJ Kohn is a rock star. In SEO, I have learned over time that there are rarely absolutes like always do this or never do that. I based my answer on how you posited the question.
If you read AJ's post you will note that the rel=canonical issue comes up with others commenting and not in the body of his post. Yes, if the page is superfluous like a cart page or a contact page, use the robots.txt to block the crawl. But, if you have a page with rank, links, etc. that help your canonical page, how are you helping yourself by forgoing rel=canon?
I think his bigger point was that you want to be aware and to understand that the # of times you are crawled is at least partially governed by PR which is governed by all those other things we discussed. If you understand that and keep the crawl focused on better pages you help yourself.
Does that clarify a bit?
Best -
Hi, even if you use robots.txt file to block these pages, Google can still pick the references of these pages from third-party websites and can crawl from there. Such pages will not have the description snippet in the search results and instead will show text that reads:
A description of this result is not available because of this site's robots.txt.
So, to fully stop Google from crawling these pages, you can go in for the page-level meta robots tag along with the robots.txt method. The page-level robots meta tag complements robots.txt method.By the way, robots.txt file can definitely save you some crawl budget. I don't think you should be thinking much about crawl budget though, as long as your website is super-easy to crawl with simple text-based internal links and stuff like, super-fast servers etc.,
Those my my two cents my friend.
Best regards,
Devanur Rafi
-
Thanks for the response, Robert.
I have read lots of SEO advice on maximizing your "crawl budget" - making sure your internal link system is built well to send the bots to the right pages. According to my research, since bots only spend a certain amount of time on your site when they are crawling, it is important to do whatever you can to ensure that they don't "waste time" on pages that are not important for SEO. Just as one example, see this post from AJ Kohn.
Do you disagree with this whole approach?
-
Yair
I think that the canonical is the better option. I am unsure as to your use of the term "crawl budget," in that there is no fixed number of times a page or a site will be crawled versus a second similar site for example. I have a huge reference site that is crawled every couple of days and I have small sites of ten pages that are crawled weekly or less. It is dependent on the traffic and behaviors of that traffic (which would include number of inbound links, etc.) and on things like you re-submitting sitemap, etc.
The canonical tag was created to provide the clarification to the search engine as to what you considered to be the relevant page. Go ahead and use it.Best
Robert
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
-
If my website do not have a robot.txt file, does it hurt my website ranking?
After a site audit, I find out that my website don't have a robot.txt. Does it hurt my website rankings? One more thing, when I type mywebsite.com/robot.txt, it automatically redirect to the homepage. Please help!
Intermediate & Advanced SEO | | binhlai0 -
Rel=canonical
My website is built around a template, the hosting site say I can only add code into the body of the webpage not the header, will this be ok for rel=canonical If it is my next question is redundant but as there is only one place to put it which urls do I need to place in the code http://domain.com, www.domain.com or http://www.domain.com the /default.asp option for my website does not seem to exist, so I guess is not relevant thanks
Intermediate & Advanced SEO | | singingtelegramsuk0 -
Using Canonical on home page
Our home page has the canonical tag pointing to itself (something from wordpress i understand). Is there any positive or negative affect that anyone is aware of from having pages canonical'ed to themselves?
Intermediate & Advanced SEO | | halloranc0 -
Blocking poor quality content areas with robots.txt
I found an interesting discussion on seoroundtable where Barry Schwartz and others were discussing using robots.txt to block low quality content areas affected by Panda. http://www.seroundtable.com/google-farmer-advice-13090.html The article is a bit dated. I was wondering what current opinions are on this. We have some dynamically generated content pages which we tried to improve after panda. Resources have been limited and alas, they are still there. Until we can officially remove them I thought it may be a good idea to just block the entire directory. I would also remove them from my sitemaps and resubmit. There are links coming in but I could redirect the important ones (was going to do that anyway). Thoughts?
Intermediate & Advanced SEO | | Eric_edvisors0 -
Is it ok to use both 301 redirect and rel="canonical' at the same time?
Hi everyone, I'm sorry if this has been asked before. I just wasn't able to find a response in previous questions. To fix the problems in our website regarding duplication I have the possibility to set up 301's and, at the same time, modify our CMS so that it automatically sets a rel="canonical" tag for every page that is generated. Would it be a problem to have both methods set up? Is it a problem to have a on a page that is redirecting to another one? Is it advisable to have a rel="canonical" tag on every single page? Thanks for reading!
Intermediate & Advanced SEO | | SDLOnlineChannel0 -
Is there a reason to put a canonical to yourself? Interesting case...
Hi, I was looking at BlueNile (biggest diamonds online dealer in the world) since I was wondering how they dealt with similar products and with sold products. Each diamond that is sold is unique. Once it is sold it is unavailable for sale. Also, all diamonds are VERY similar so they should also find a way to handle duplication in content. Look at the following 2 pages: http://www.bluenile.com/round-diamond-1-carat-or-less-ideal-cut-g-color-vs1-clarity_LD02360835 http://www.bluenile.com/round-diamond-1-carat-or-less-ideal-cut-g-color-vs1-clarity_LD02366155 The pages are practically identical and in the "view source" I noticed that they add a canonical tag to themselves... Any thoughts on that? Thanks
Intermediate & Advanced SEO | | BeytzNet0 -
Use of rel=canonical to view all page & No follow links
Hey, I have a couple of questions regarding e-commerce category pages and filtering options: I would like to implement the rel=canonical to the view all page as suggested on this article on googlewebmastercentral. If you go on one of my category pages you will see that both the "next page link" and the "view all" links are nofollowed. Is that a mistake? How does nofoolow combines with canonical view all? Is it a good thing to nofollow the "sorty by" pages or should I also use Noindex for them?
Intermediate & Advanced SEO | | Ypsilon0 -
Should I robots block site directories with primarily duplicate content?
Our site, CareerBliss.com, primarily offers unique content in the form of company reviews and exclusive salary information. As a means of driving revenue, we also have a lot of job listings in ouir /jobs/ directory, as well as educational resources (/career-tools/education/) in our. The bulk of this information are feeds, which exist on other websites (duplicate). Does it make sense to go ahead and robots block these portions of our site? My thinking is in doing so, it will help reallocate our site authority helping the /salary/ and /company-reviews/ pages rank higher, and this is where most of the people are finding our site via search anyways. ie. http://www.careerbliss.com/jobs/cisco-systems-jobs-812156/ http://www.careerbliss.com/jobs/jobs-near-you/?l=irvine%2c+ca&landing=true http://www.careerbliss.com/career-tools/education/education-teaching-category-5/
Intermediate & Advanced SEO | | CareerBliss0