In SEO, understanding canonicalization and being able to set canonical URLs correctly is essential. But what is a canonical URL, why is it important, and how do you create them? This article gives you the lowdown on all that, and more.
When websites get bigger, it’s almost inevitable that there will be duplicate or very similar content that is available via multiple URLs. When multiple URLs can rank for a certain keyword it’s difficult for search engines to know which URL to send traffic to. This conundrum led to the creation of canonical tags.
Canonical tags were originally introduced in February 2009 as a collaborative effort (one of the very few!) from Google, Bing and Yahoo! to help webmasters deal with issues related to duplicate content. They allow webmasters to decide on a preferred URL, which is what we call a canonical URL.
While many people use the terms “canonical tag” and “canonical URL” synonymously, this is incorrect.
Canonical tags are the most commonly used way of setting a preferred URL, but they are not the only way. According to Google, a canonical URL is simply “the URL of the page that Google believes best represents a group of duplicate pages on your site”. It is useful to note that not all websites need canonical URLs as much as others. Smaller websites with simple content and pages that fit in multiple categories are less likely to need them than large and complex websites.
If you have two identical pages under different URLs and neither is set as the canonical URL, then search engines will simply decide for themselves.
Let’s say you have a post or product that can be found under two different categories and as such, exists in two different URLs, for example:URL 1: https://exampleshop.com/shirts/red-long-sleeve/URL 2: https://exampleshop.com/long-sleeves/red-long-sleeve/By choosing one of these links as a canonical URL, you are telling the search engine which one you want it to show in search results, overriding the automatic choice it may make.
Canonicals are also capable of directing search engines to the original version of an article. This is useful if you’ve written an article for another website but would like to post a copy on yours as well. You could agree to post the article on your own website, but with a canonical to the original, on theirs.
Canonicals organise multiple URLs under one master URL, making it easier to track the metrics of a specific product or topic. This is especially useful when you need to report on performance to your client.
Canonical URLs consolidate information for individual URLs into one master URL. Syndicated content that has been posted on other domains is also consolidated into the page ranking of your preferred URL.
There are 5 known ways of setting canonical URLs, known as canonicalization signals.
In their words:
“We don’t guarantee that we’ll consider the sitemap URLs to be canonical, but it is a simple way of defining canonicals for a large site, and sitemaps are a useful way to tell Google which pages you consider most important on your site.”
Canonicals are really quite simple to implement, but there are 5 golden rules that you should always follow.
Now that you understand what a canonical URL is and how to implement them, you should be on your way to optimising your site for better rankings. Canonical URLs are a simple but essential tool in an SEOs toolbox and they shouldn’t be neglected.
