How to Use Canonical Tags for Beginners
You need to understand what canonical tags are and how to use them properly. Implementing canonical incorrectly could negatively impact your website rankings.
Canonical tags were first introduced in 2009,and they have helped webmasters solve problems when it comes to duplicate content accessible on different URLs. However, if you’re using the canonical tag, you need to know what it is, how it works on your website, and how to implement it correctly.
Read our guide for canonical tags for beginners for everything you need to know.
Canonical Tags for Beginners — Your Go-To Guide
First things first, what is a canonical tag or canonical URL? A canonical tag is an HTML element that tells the search engine to focus on the page marked with the canonical URL for ranking purposes and ignore all other versions of the page.
This is useful when you have multiple pages with similar content, and you don’t want them to be flagged as duplicate content. These tags can be found in the header code of your page. The URL either points to it's own or another URL to consolidate signals to search engines.
A canonical link or URL is the version you want Google and your audience to see instead of other duplicate pages. Luckily, canonical tags are an easy-to-use syntax that should be placed under the <head> section of your web page.
It looks like this:
<link rel=“canonical” href=“https://website.com/test-page/” />
Why Do Canonical Tags Matter For SEO?
When there are versions of the same page, it makes finding the right one difficult to index, which means search engines won’t know which page to rank higher to viewers. Duplicate pages also cause cannibalization issues, meaning that the page's value gets split between multiple pages within the same content. Bottom line — none of the pages will get a ranking advantage.
Duplicate content on your website can also affect your crawl budget. This is because search engines will waste time crawling the same page’s multiple versions instead of identifying important content.
Avoid duplicate content, so search engines will crawl pages you want to rank. However, if your website has less than a few thousand URLs, it will likely be crawled just fine. But, if you are facing issues because of the crawl budget, canonical tags can help you show search engines which version they are supposed to index and rank.
Search engines will use their discretion if you don’t add a canonical URL coupled with their algorithm to identify the page they think is the best version. This could be an issue if they select the wrong version. Therefore, make sure that you use best practices for canonical tags to mitigate the risk of search engines using an undesirable version.
Duplicate Content and Multiple URLs with Same Content
Having duplicate content on your website can negatively affect your rankings, causing you to lose traffic to your site. Here’s why:
- Search engines want to provide the best experience for users, meaning they will not show multiple versions of the same content. Instead, they have algorithms that will choose the “best” version. If this happens to you, then the visibility of your pages could be diluted.
- Duplicate pages also dilute the link equity of your pages, like other websites that might be linking to your pages, will not know which page to connect to and might link to multiple pages, making each page less valuable than if they were all pointing to one page.
Duplicate content causes issues for search engines because they don’t know which version should be included or excluded from the index. Ultimately it could lead to your pages not showing up on search engine results at all.
Best Practices For Canonical Tags For Beginners
Though we’re throwing a lot of information at you, it’s not difficult to implement canonicals. Here are some practices to follow as you’re setting them up.
Use Absolute URLs
Don’t use relative paths for rel=“canonical” link element. Instead, use these structures:
- <link rel=“canonical” href=”/sample-page/” />
- <link rel=“canonical” href=“https://website.com/test-page/” />
Tips for Using Lowercase URLs
There is a chance that search engines treat lowercase and uppercase URLs as different. Therefore, use lowercase URLs on your site, and make sure you do the same for your canonical tags as well.
Correct Version Of The Domain (HTTPS vs. HTTP)
Are you switching over to SLL? Don’t declare non-SSL URLs in the canonical tags. It might lead to unexpected results and a lot of confusion. If your website is on a secure domain, use this format:
<link rel=“canonical” href=“http://example.com/test-page/” />
Use Self-Referential Canonical Tag
A self-referential canonical tag is a tag that points to the same page. It’s not mandatory, but it is recommended. It makes it clear to the search engine which pages should be indexed. There could be different URL variations, but all that can be cleared up using a rel canonical tag.
So, if the URL is https://example.com/test-page, the self-referential canonical will be:
<link rel=“canonical” href=“https://example.com/test-page” />
Some popular CMS that will automatically add a self-referencing URL. However, in the case of custom CMS, you might need a developer to hardcode this.
Canonical Tag Per Page
Several canonical tags on page, each of them will be ignored by the search engines.
How to Implement the rel=canonical Tag
Canonical URLs using HTML Tag
The best way (and the simplest way) to specify the canonical URL is using the rel=canonical tag. Add this to your duplicate page’s <head> section:
<link rel=“canonical” href=“https://website.com/canonical-page/” />
Setting a Canonical tag in HTTP Header
There isn’t a header section for documents like PDFs to place canonical tags. However, you can add the canonical code in the header section of your PHP file.
Canonical URLs in Sitemaps
Google recommends not including non-canonical pages in sitemaps. Only list canonical URLs because Google uses the pages in the sitemaps as recommended canonicals. Sitemaps can help larger websites tell the search engine which pages you consider most important.
Setting Canonicals with 301 redirects
Using the canonical tag to divert traffic from a dupliacte URLs with 301 rediects. Select the right canocical tag and direct duplicate one to that version. Or www/no-www and HTTPs/HTTP versions of the website.
Canonical URLs on Magento and Magento 2
Looking to set a canonical URL on Magento? Here’s what to do:
- Sign in to the ‘Admin Panel’.
- Next, ‘Settings’ and ‘Configuration’.
- Catalog’ option from the drop-down menu.
- Open the ‘Search Engine Optimization’ section.
- Link Meta Tag for Categories – ‘Yes’; Use Canonical Link Meta Tag for Products – ‘No’;
- To only index the product page, you have to complete the following settings: Use Canonical Link Meta Tag for Categories – ‘No’; Use Canonical Link Meta Tag for Products – ‘Yes’;
- To index products and categories, you have to enable both options: Use Canonical Link Meta Tag for Categories – ‘Yes’; Use Canonical Link Meta Tag for Products – ‘Yes’;
Once you are done, make sure you clear the cache and save the changes.
Canonical URLs on WordPress
Install Yoast SEO if you want to set the canonical URL on WordPress. It will automatically add the self-referencing canonical tags. Use the ‘Advanced’ section to set the custom canonicals.
Canonical URL on Wix
The canonical URL is automatically created for all pages on Wix. Use the Advanced SEO tab if you want to change the canonical tab or have multiple URLs going to the same page.
Setting a Canonical URL on Shopify
Are you using Shopify? You’ll be happy to know that self-referencing canonical URLs are automatically added to blog posts and products. Edit the template files directly if you want to set custom canonical URLs.
Common Canonicalization Mistakes and Fixes
Canonical Points To 4XX
You will get a warning if you have pages canonicalized to a 4XX URL. This is because search engines won’t index these pages and ignore any canonical tags that point to such pages. So make sure you review the pages and use links to the working page to replace dead canonical links.
Canonical Points To 5XX
Similar to 4XX, 5XX codes mean that there are server issues that will lead to a page your audience can’t access. Search engines will ignore them if you canonicalize them, and they won’t be indexed. Replace all incorrect canonical URLs and check for server misconfigurations.
Canonical Points To Redirect
If pages are canonicalized to a 301 redirected URL, this is cause for concern. Although the canonicals must have an authoritative version of the page, sending them to a redirect URL will cause search engines to ignore or misinterpret the canonical.
Duplicate Pages Without Canonical
Since there is no canonical URL, search engines will try to identify the most appropriate version (it’s better to give them the page you want to rank).
Canonical Url Has No Incoming Internal Links
An orphan page is when your specified canonical URLs don’t have any internal links, and it is therefore inaccessible to your visitors and search engines. Instead, they can be redirected to the web page’s non-canonical version.
Non-Canonical Page In Sitemap
If you have non-canonical pages in your sitemap, Google might consider these pages as suggested canonicals. Fix this issue by removing non-canonical URLs from the sitemap.
Non-Canonical Pages Specified As The Canonical Ones
This issue is triggered when you specify a canonical URL that is also canonicalized to a different page, resulting in a canonical chain — which will confuse search engines. For example, if A is pointing to B, and B is canonicalized to C, you need to replace A’s link with C’s canonical link.
Canonical from HTTPS to HTTP
This issue occurs when you have secure pages (HTTPS) that have a non-secure version (HTTP) as canonical. Solve this problem when you redirect the HTTP page to its HTTPS equivalent. If you can’t do this, you can add the HTTP version’s ref=”canonical” link to the HTTPS one.
Canonical from HTTP to HTTPS
This warning is the opposite of the one above. Fix it by implementing a 301 redirect from HTTP to HTTPS and then replace the HTTP version’s internal links directly to the HTPPS version.
Non-Canonical Page Receives Organic Traffic
If your non-canonical pages are continually showing up on search results and receiving organic search traffic, it means that search engines are ignoring your specified canonical. First, fix this by ensuring that rel=canonical tags are correctly set up. Then, you should check the URL inspection tool to see if the URL you specified are considered canonical.
Blocking The Canonicalized URL via robots.txt
If you block a canonicalized URL in robots.txt, search engines won’t crawl it. Unfortunately, this prevents search engines from transferring link equity from non-canonical to canonical URLs.
Setting The Canonicalized URL to ‘noindex’
Don’t rel=canonical and noindex as they are contradictory instructions. Google prioritizes the canonical tag over the ‘noindex’ tag. If you want to canonical and noindex a URL, you can use a 301 redirect or rel=canonical.
How To Audit Canonical Tags For Seo
When you’re auditing canonical tags, there are several things you should look out for for the best SEO performance.
Look for whether or not the page already has a canonical tag, and if it does, does it point to the right page? Is that page indexable and crawlable?
You can inspect and audit canonical tags by checking the source code (right-click on the browser and hit ‘view-source’). There are also several SEO site audit software programs that can help you audit your tags in bulk.
By now, you realize that canonicalization is an integral part of your SEO efforts. Without proper implementation, it’s likely that your website won’t be performing as well as it could. Hopefully, this article has helped you understand what canonical URLs are, what canonical tags do, and how to spot mistakes and fiz=x canonicalization issues. However, if you’re struggling with using canonical tags properly, we can help!
Reach out to our team today and let us help you audit your site and get your site optimized properly so you can rank higher and get in front of your target audience. Get started here.
Written by Aaron Rains March 4th 2022