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
-
H Tags in Menu
Hi I am checking the H2 tags on this page https://www.key.co.uk/en/key/dollies-load-movers-door-skates I have noticed my dev team have implemented H2's on the categories in the menu. Will this completely confuse Google as to what that page is about? In my opinion those links shouldn't be heading tags at all
Intermediate & Advanced SEO | | BeckyKey0 -
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 -
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 -
Fast/Easy Way to Implement Canonical tags in Bulk in Magento CMS?
Hello Amazing SEO Community! Quick Q for a client with a TON of duplicate content. (yikes!) My client is currently undertaking a large SEO project around canonical tagging for their thousands of duplicate pages. Currently, one product sits on multiple URLs and they are being indexed as different pages (with the same content). The issue is found across all products and other pages, and across their international sites as well. One core challenge they face now is lack of time/resources from their developer side. The solution we see to the duplicate content is to manually add a canonical tag to each of our tens of thousands of pages. Their content management system is Magento. Has anyone ever tackled canonicalization for a large site that uses Magento? Any more efficient solutions to manual tagging is ideal. Thanks in advance for your input. -Bonnie
Intermediate & Advanced SEO | | accpar0 -
Should I use **tags or h1/h2 tags for article titles on my homepage**
I recently had an seo consultant recommend using tags instead of h1/h2 tags for article titles on the homepage of my news website and category landing pages. I've only seen this done a handful of times on news/editorial websites. For example: http://www.muscleandfitness.com/ Can anyone weigh in on this?
Intermediate & Advanced SEO | | blankslatedumbo0 -
tags inside <a>tags - is this bad?</a>
Hi, I'm currently redesigning my website, and in many places, I've now decided to make links a little bit more obvious for the user, using tags within a <a>tag in order to make the entire block of text clickable. I was just wondering if this could have a negative impact in the search engines. My gut feeling is no, since I'm actually improving usability, but I guess it could have an impact on how Google looks at the anchor text? An example of the HTML is as follows: </a> <a></a> <a></a> [Cristal Night Club Hotels <address>1045 5th Street
Intermediate & Advanced SEO | | mjk26
Miami Beach, FL33139</address> 6.4 miles from Miami Dade County Auditorium](http://localhost:8080/frontend/venue-hotels/cristal-night-club-hotels/301022 "Hotels near Cristal Night Club") Thanks for your thoughts and comments, Best wishes Mike0 -
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 | | mhans1 -
Can a XML sitemap index point to other sitemaps indexes?
We have a massive site that is having some issue being fully crawled due to some of our site architecture and linking. Is it possible to have a XML sitemap index point to other sitemap indexes rather than standalone XML sitemaps? Has anyone done this successfully? Based upon the description here: http://sitemaps.org/protocol.php#index it seems like it should be possible. Thanks in advance for your help!
Intermediate & Advanced SEO | | CareerBliss0