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.
How does a canonical work and is it necessary to also have a no index, follow tag in place?
-
Across our site, we have canonical tags in place for URLs that contain duplicate content and for URLs without a trailing slash since we are using URLs WITH a trailing slash for all URLs across our site. We also recently added a no index, follow tag to all non-canonical URLs since we noticed a high number of duplicate content URLs in Google Webmaster Tools.
The first part of my question is: How does a canonical work? Does the robot read the canonical and immediately go to the canonical URL or does it continue to read past the canonical tag and get to the no index, follow tag if there is one present?
The second part of my question is: Is it necessary to have both a canonical tag and no index, follow tag in place? Or should the canonical tag be sufficient to avoid duplicate content?
And lastly, if both a canonical tag and no index, follow tag are in place, should they be in a specific order? Canonical tag first then no index, follow tag second or no index, follow tag first then canonical tag second?
I would appreciate any insight you can give. Thank you!
-
Thank you for you responses and advice!
-
Very nice addition John.
-
Ryan, spot on as always.
One other thing, it sounds like some of the canonicals you're placing on pages would be better suited to 301 redirects, like correcting a URL for not having a trailing slash or not. If you can avoid using canonicals and use 301 redirects instead, that's the preferred method for resolving duplicate content issues. Canonicals are more for when there are parameters on the URLs, and you can't get away from serving the pages with those parameters.
-
How does a canonical work? Does the robot read the canonical and immediately go to the canonical URL or does it continue to read past the canonical tag and get to the no index, follow tag if there is one present?
The first thing to understand is the canonical tag is a suggestion, not an order. While a search engine will usually honor the canonical tag, there are instances where Google or other SEs may determine the canonical tag is not being used correctly so they disregard the canonical tag. Based on this understanding, yes the robot will read the entire page regardless of the canonical tag status.
Is it necessary to have both a canonical tag and no index, follow tag in place? Or should the canonical tag be sufficient to avoid duplicate content?
The two tags you mention conflict. You would never use both tags on the same page.
Noindex means you do not wish the page to appear in the search index. The canonical tag means you do wish the content to be included in the search index, but use the canonical URL in the index.
if both a canonical tag and no index, follow tag are in place, should they be in a specific order?
The order of meta tags does not matter. If a page was marked with both a canonical tag and a noindex tag, the noindex tag would take effect and the page would not be indexed, so the canonical tag would not have any effect.
In short, you want to use the canonical tag to resolve duplicate content issues, not the noindex tag.
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 -
Google Ignoring Canonical Tag for Hundreds of Sites
Bazaar Voice provides a pretty easy-to-use product review solution for websites (especially sites on Magento): https://www.magentocommerce.com/magento-connect/bazaarvoice-conversations-1.html If your product has over a certain number of reviews/questions, the plugin cuts off the number of reviews/questions that appear on the page. To see the reviews/questions that are cut off, you have to click the plugin's next or back function. The next/back buttons' URLs have a parameter of "bvstate....." I have noticed Google is indexing this "bvstate..." URL for hundreds of sites, even with the proper rel canonical tag in place. Here is an example with Microsoft: http://webcache.googleusercontent.com/search?q=cache:zcxT7MRHHREJ:www.microsoftstore.com/store/msusa/en_US/pdp/Surface-Book/productID.325716000%3Fbvstate%3Dpg:8/ct:r+&cd=2&hl=en&ct=clnk&gl=us My website is seeing hundreds of these "bvstate" urls being indexed even though we have a proper rel canonical tag in place. It seems that Google is ignoring the canonical tag. In Webmaster Console, the main source of my duplicate titles/metas in the HTML improvements section is the "bvstate" URLs. I don't necessarily want to block "bvstate" in the robots.txt as it will prohibit Google from seeing the reviews that were cutoff. Same response for prohibiting Google from crawling "bvstate" in Paramters section of Webmaster Console. Should I just keep my fingers crossed that Google honors the rel canonical tag? Home Depot is another site that has this same issue: http://webcache.googleusercontent.com/search?q=cache:k0MBLFcu2PoJ:www.homedepot.com/p/DUROCK-Next-Gen-1-2-in-x-3-ft-x-5-ft-Cement-Board-172965/202263276%23!bvstate%3Dct:r/pg:2/st:p/id:202263276+&cd=1&hl=en&ct=clnk&gl=us
Intermediate & Advanced SEO | | redgatst1 -
Null Alt Image Tags vs Missing Alt Image Tags
Hi, Would it be better for organic search to have a null alt image tag programatically added to thousands of images without alt image tags or just leave them as is. The option of adding tailored alt image tags to thousands of images is not possible. Is having sitewide alt image tags really important to organic search overall or what? Right now, probably 10% of the sites images have alt img tags. A huge number of those images are pages that aren Thanks!
Intermediate & Advanced SEO | | 945010 -
Meta Robot Tag:Index, Follow, Noodp, Noydir
When should "Noodp" and "Noydir" meta robot tag be used? I have hundreds or URLs for real estate listings on my site that simply use "Index", Follow" without using Noodp and Noydir. Should the listing pages use these Noodp and Noydr also? All major landing pages use Index, Follow, Noodp, Noydir. Is this the best setting in terms of ranking and SEO. Thanks, Alan
Intermediate & Advanced SEO | | Kingalan10 -
Links from non-indexed pages
Whilst looking for link opportunities, I have noticed that the website has a few profiles from suppliers or accredited organisations. However, a search form is required to access these pages and when I type cache:"webpage.com" the page is showing up as non-indexed. These are good websites, not spammy directory sites, but is it worth trying to get Google to index the pages? If so, what is the best method to use?
Intermediate & Advanced SEO | | maxweb0 -
Partial duplicate content and canonical tags
Hi - I am rebuilding a consumer website, and each product page will contain a unique product image, and a sentence or two about the product (and we tend to use a lot of the same words in different ways across products). I'd like to have a tabbed area below the product info that talks about the overall product line, and this content would be duplicate across all the product pages (a "Why use our products" type of thing). I'd have this duplicate content also living on its own URL's so they can be found alone in the SERP's. Question is, do I need to add the canonical tag to this page, since there's partial duplicate content on the product pages? And if I did that, would my product pages go un-indexed?? I understand how to handle completely duplicated content, it's the partial duplicate that I'm having difficulty figuring out.
Intermediate & Advanced SEO | | Jenny10 -
Rel=canonical tag on original page?
Afternoon All,
Intermediate & Advanced SEO | | Jellyfish-Agency
We are using Concrete5 as our CMS system, we are due to change but for the moment we have to play with what we have got. Part of the C5 system allows us to attribute our main page into other categories, via a page alaiser add-on. But what it also does is create several url paths and duplicate pages depending on how many times we take the original page and reference it in other categories. We have tried C5 canonical/SEO add-on's but they all seem to fall short. We have tried to address this issue in the most efficient way possible by using the rel=canonical tag. The only issue is the limitations of our cms system. We add the canonical tag to the original page header and this will automatically place this tag on all the duplicate pages and in turn fix the problem of duplicate content. The only problem is the canonical tag is on the original page as well, but it is referencing itself, effectively creating a tagging circle. Does anyone foresee a problem with the canonical tag being on the original page but in turn referencing itself? What we have done is try to simplify our duplicate content issues. We have over 2500 duplicate page issues because of this aliasing add-on and want to automate the canonical tag addition, rather than go to each individual page and manually add this tag, so the original reference page can remain the original. We have implemented this tag on one page at the moment with 9 duplicate pages/url's and are monitoring, but was curious if people had experienced this before or had any thoughts?0 -
Should I Allow Blog Tag Pages to be Indexed?
I have a wordpress blog with settings currently set so that Google does not index tag pages. Is this a best practice that avoids duplicate content or am I hurting the site by taking eligible pages out of the index?
Intermediate & Advanced SEO | | JSOC0