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
-
Moving html site to wordpress and 301 redirect from index.htm to index.php or just www.example.com
I found page duplicate content when using Moz crawl tool, see below. http://www.example.com
Intermediate & Advanced SEO | | gozmoz
Page Authority 40
Linking Root Domains 31
External Link Count 138
Internal Link Count 18
Status Code 200
1 duplicate http://www.example.com/index.htm
Page Authority 19
Linking Root Domains 1
External Link Count 0
Internal Link Count 15
Status Code 200
1 duplicate I have recently transfered my old html site to wordpress.
To keep the urls the same I am using a plugin which appends .htm at the end of each page. My old site home page was index.htm. I have created index.htm in wordpress as well but now there is a conflict of duplicate content. I am using latest post as my home page which is index.php Question 1.
Should I also use redirect 301 im htaccess file to transfer index.htm page authority (19) to www.example.com If yes, do I use
Redirect 301 /index.htm http://www.example.com/index.php
or
Redirect 301 /index.htm http://www.example.com Question 2
Should I change my "Home" menu link to http://www.example.com instead of http://www.example.com/index.htm that would fix the duplicate content, as indx.htm does not exist anymore. Is there a better option? Thanks0 -
How (or if) to apply re canonical tags to Shopify?
Anyone familiar with Shopify will understand the problems of their directory structure. Every time you add a product to a 'collection' it essentially creates a duplicate. For example... https://www.domain.com/products/product-slim-regular-bikini may also appear as: https://www.domain.com/collections/all/products/product-slim-regular-bikini https://www.domain.com/collections/new-arrivals/products/product-slim-regular-bikini https://www.domain.com/collections/bikinis/products/product-slim-regular-bikini etc, etc It's not uncommon to have up to six duplicates of each product. So my question is twofold: Firstly, should I worry about this from an SEO point of view? I understand the desire to minimise potential duplicate content issues and also in focussing the 'juice' on just one page per product. But I also planned on trying to build the authority of the collection pages. If I request Google not to index the product pages which link off the collections, does this not devalue these collections pages? Secondly, I understand the correct way to fix these is using 'rel canonical' tags, but I'm not clear about HOW to actually do this. Shopify support has not been very helpful. They have provided two different instructions, so just added to the confusion (see below). Shopify instruction #1: Add the following to the theme.liquid file... <title><br />{{ page_title }}{% if current_tags %} – tagged "{{ current_tags | join: ', ' }}"{% endif %}{% if current_page != 1 %} – Page {{ current_page }}{% endif %}{% unless page_title contains shop.name %} – {{ shop.name }}{% endunless %}<br /></title>
Intermediate & Advanced SEO | | muzzmoz
{% if page_description %} {% endif %} Shopify instruction #2: Add the following to each individual product page... So, can anyone help clarify: The best strategic approach to this inherent SEO issue with Shopify (besides moving to another platform!)? and If 'rel canonical' tags is the way to go, exactly where and how to apply them? Regards, Murray1 -
Do you add 404 page into robot file or just add no index tag?
Hi, got different opinion on this so i wanted to double check with your comment is. We've got /404.html page and I was wondering if you would add this page to robot text so it wouldn't be indexed or would you just add no index tag? What would be the best approach? Thanks!
Intermediate & Advanced SEO | | Rubix0 -
Follow or nofollow to subdomain
Hi, I run a hotel booking site and the booking engine is setup on a subdomain.
Intermediate & Advanced SEO | | vmotuz
The subdomain is disabled from being indexed in robots.txt Should the links from the main domain have a nofollow to the subdomain? What are you thoughts? Thanks!0 -
Google places keyword variations
Hi all, I have a site that is ranking #1 in Google Places for its main <city><keyword>search... but it does not rank for any of its basic keyword variations, which I find very confusing.</keyword></city> ie (just an example) Chicago Caterer (ranked #1 in google places)
Intermediate & Advanced SEO | | x2264983x
Chicago Caterers (not ranked in google places)
Chicago Catering (not ranked in google places)
Chicago Catering Company (not ranked in google places)
Chicago Catering Companies (etc..) How can I secure a google places ranking for these simple keyword variations? Do I build links to the google plus page using that anchor text? Do I get citations that contain that keyword somewhere on the page? Do I optimize for these keyword variations on the actual website itself? (not the places listing). Obviously I don't stuff these keywords into the google places listing. Any help would be much appreciated!0 -
How do you de-index and prevent indexation of a whole domain?
I have parts of an online portal displaying in SERPs which it definitely shouldn't be. It's due to thoughtless developers but I need to have the whole portal's domain de-indexed and prevented from future indexing. I'm not too tech savvy but how is this achieved? No index? Robots? thanks
Intermediate & Advanced SEO | | Martin_S0 -
H2 Tag Backlink - is this safe?
I have found that my site is getting a link from a good site, but my concern is that the link is in a H2 tag in the footer of the front page of the site Would getting a link from a site wrapped in H2 tags be safe? The anchor is my sites brand name
Intermediate & Advanced SEO | | JohnPeters0 -
How important is the number of indexed pages?
I'm considering making a change to using AJAX filtered navigation on my e-commerce site. If I do this, the user experience will be significantly improved but the number of pages that Google finds on my site will go down significantly (in the 10,000's). It feels to me like our filtered navigation has grown out of control and we spend too much time worrying about the url structure of it - in some ways it's paralyzing us. I'd like to be able to focus on pages that matter (explicit Category and Sub-Category) pages and then just let ajax take care of filtering products below these levels. For customer usability this is smart. From the perspective of manageable code and long term design this also seems very smart -we can't continue to worry so much about filtered navigation. My concern is that losing so many indexed pages will have a large negative effect (however, we will reduce duplicate content and be able provide much better category and sub-category pages). We probably should have thought about this a year ago before Google indexed everything :-). Does anybody have any experience with this or insight on what to do? Thanks, -Jason
Intermediate & Advanced SEO | | cre80