Canonization is a word that is unlikely to pass most people’s lips.
In SEO parlance, however, this is a significant issue, and canonical issues can hurt SEO performance. There are some pitfalls that are actually very easy to fall into and I want to share some of the more common issues that you may not realize are affecting your site.
What is a canonical problem?
Canonical issues are really duplicate content issues, but with a fancy name. Duplicate content is where multiple instances of a web page are available at multiple URLs. This may affect multiple domains, but this is an issue that can occur on a single site. For example, if a product is available in multiple categories on an e-commerce site, the product description/images/etc. will be replicated to multiple URLs.
Search engines see this as duplicate content and they don’t like it. No search engine wants its results pages to be filled with identical web pages. So they will usually choose one instance of the same content and ignore the others. This “master” version is known as the canonical version and you can use canonical tags to help guide search engines.
Many talk about duplicate content penalties, but I prefer to refer to it as a duplicate content filter – search engines will ignore duplicate content in favor of a “canonical” URL.
Why do we care?
There are a number of reasons why you need to pay attention to your site’s canonical issues.
First of all, you might prefer one URL to show up in SERPS over another – particularly if one looks friendly and nice and clean, compared to another that’s very code-based or complicated. By using canonical tags, you can control which URL is chosen as the master.
Link juice… Now I have your attention – you don’t want to undo all your hard link building work, do you? Without using canonical tags, you risk diluting the value of links that point to multiple versions of the same content. This means that the link juice for all duplicate pages is merged, which is beneficial for search rankings.
If you have competing URLs, it’s more complicated to track stats like sessions, visitors, or engagement across all pages. Setting up a canonical tag doesn’t guarantee that other pages won’t get any visits, but it will help direct traffic to the one you prefer.
Organizations that have multiple sites can choose to upload their content to all of their platforms. There’s absolutely nothing wrong with that from a user perspective, but they really should prioritize one site over another for SERP purposes.
Google doesn’t crawl every page every day. Google has allocated a crawl budget to each site which determines how often it returns to search for new content and how deep its spiders or crawlers penetrate your site with each visit. By using canonical tags, you won’t waste any of that budget crawling duplicate pages.
Here we look at five different types of canonical issues for site owners to watch out for. The first two impact the entire site.
1. www vs non-www
Like us, you may have chosen to remove the “World Wide Web” prefix from your site and simply opted for http://domain.com, i.e. https://browsermedia.agency/. However, you can’t control what users search for, or update all of your old links. As this is a site-wide issue, it means that every page on the site would be duplicated unless you configured your server and redirects correctly. Sip.
2. https versus http
If your site is secured with an SSL certificate (a type of digital certificate that provides authentication for a website and allows an encrypted connection), it changes from http to https. However, unless you ensured that only https is available, you will have created duplicates of each page.
3. Desktop and Mobile Websites
Overall, organizations that have separate mobile and desktop sites are rare, but if you’re one, so is it. Posting identical content on both sites will result in the same canonical issue.
4. Dynamic URLs
Content management systems are based on the principle of generating web pages by feeding models with content from a database. Exactly how this happens will vary and some platforms will use URL parameters to control the content of a page.
If you have content posted on multiple pages, it can be easy to inadvertently create duplicate content. Using canonical tags will allow you to point all duplicate pages to an instance of this dynamic URL.
5. Syndicated Content
Most PR and content professionals are aware of certain sites that distribute content. A tactical sale to a reporter on a particular news website may mean your content appears in multiple outlets. It’s a win from a brand awareness perspective, but it introduces potential duplicate content issues.
Until the reporter has been promised exclusivity, it’s worth considering if a canonical tag could be added to point to the original source (your site).
As always, Google reserves the right to make its own decisions about the content it serves users based on what it deems their intent. But marking content as canonical can often point content in the right direction.