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.
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
-
Canonical and Alternate Advice
At the moment for most of our sites, we have both a desktop and mobile version of our sites. They both show the same content and use the same URL structure as each other. The server determines whether if you're visiting from either device and displays the relevant version of the site. We are in a predicament of how to properly use the canonical and alternate rel tags. Currently we have a canonical on mobile and alternate on desktop, both of which have the same URL because both mobile and desktop use the same as explained in the first paragraph. Would the way of us doing it at the moment be correct?
Intermediate & Advanced SEO | | JH_OffLimits3 -
Should I use change of address when moving to subdomain
Hi guys So we had a domain that was only for one country, www.example.com 1 year later we decided to go to another country so we will have all the current website under a country subdomain like : ae.example.com we did a 301 redirect
Intermediate & Advanced SEO | | awrikat
Should I perform a change of address action from www.example.com to ae.example.com ? please help
Thanks0 -
When should you 410 pages instead of 404
Hi All, We have approx 6,000 - 404 pages. These are for categories etc we don't do anymore and there is not near replacement etc so basically no reason or benefit to have them at all. I can see in GWT , these are still being crawled/found and therefore taking up crawler bandwidth. Our SEO agency said we should 410 these pages?.. I am wondering what the difference is and how google treats them differently ?. Do anyone know When should you 410 pages instead of 404 ? thanks Pete
Intermediate & Advanced SEO | | PeteC120 -
Should I be using meta robots tags on thank you pages with little content?
I'm working on a website with hundreds of thank you pages, does it make sense to no follow, no index these pages since there's little content on them? I'm thinking this should save me some crawl budget overall but is there any risk in cutting out the internal links found on the thank you pages? (These are only standard site-wide footer and navigation links.) Thanks!
Intermediate & Advanced SEO | | GSO0 -
Should I use rel=canonical on similar product pages.
I'm thinking of using rel=canonical for similar products on my site. Say I'm selling pens and they are al very similar. I.e. a big pen in blue, a pack of 5 blue bic pens, a pack of 10, 50, 100 etc. should I rel=canonical them all to the best seller as its almost impossible to make the pages unique. (I realise the best I realise these should be attributes and not products but I'm sure you get my point) It seems sensible to have one master canonical page for bic pens on a site that has a great description video content and good images plus linked articles etc rather than loads of duplicate looking pages. love to hear thoughts from the Moz community.
Intermediate & Advanced SEO | | mark_baird0 -
Use of subdomains, subdirectories or both?
Hello, i would like your advice on a dilemma i am facing. I am working a new project that is going to release soon, thats a network of users with personal profiles seperated in categories for example lets say the categories are colors. So let say i am a member and i belong in red color categorie and i got a page where i update my personal information/cv/resume as well as a personal blog thats on that page. So the main site is giving the option to user to search for members by the criteria of color. My first idea is that all users should own a subdomain (and this is how its developed so far) thats easy to use and since the domain name is really small (just 3 letters) i believe subdomain worth since personal site will be easy to remember. My dilemma is should all users own a subdomain, a subdirectory or both and if both witch one should be the canonical? Since it said that search engines treat subdomains as different stand-alone sites, whats best for the main site? to show multiple search results with profiles in subdomains or subdirectories? What if i use both? meaning in search results i use search directory url for each profile while same time each profile owns a subdomains as well? and if so which one should be the canonical? Thanks in advance, C
Intermediate & Advanced SEO | | HaCos0 -
Robots.txt: Can you put a /* wildcard in the middle of a URL?
We have noticed that Google is indexing the language/country directory versions of directories we have disallowed in our robots.txt. For example: Disallow: /images/ is blocked just fine However, once you add our /en/uk/ directory in front of it, there are dozens of pages indexed. The question is: Can I put a wildcard in the middle of the string, ex. /en/*/images/, or do I need to list out every single country for every language in the robots file. Anyone know of any workarounds?
Intermediate & Advanced SEO | | IHSwebsite0 -
Blocking Dynamic URLs with Robots.txt
Background: My e-commerce site uses a lot of layered navigation and sorting links. While this is great for users, it ends up in a lot of URL variations of the same page being crawled by Google. For example, a standard category page: www.mysite.com/widgets.html ...which uses a "Price" layered navigation sidebar to filter products based on price also produces the following URLs which link to the same page: http://www.mysite.com/widgets.html?price=1%2C250 http://www.mysite.com/widgets.html?price=2%2C250 http://www.mysite.com/widgets.html?price=3%2C250 As there are literally thousands of these URL variations being indexed, so I'd like to use Robots.txt to disallow these variations. Question: Is this a wise thing to do? Or does Google take into account layered navigation links by default, and I don't need to worry. To implement, I was going to do the following in Robots.txt: User-agent: * Disallow: /*? Disallow: /*= ....which would prevent any dynamic URL with a '?" or '=' from being indexed. Is there a better way to do this, or is this a good solution? Thank you!
Intermediate & Advanced SEO | | AndrewY1
