If you are conscious about your website’s ranking in the search engine results, then one of the last things you want to find out is that you have several instances of duplicate content in your site. In case you do find an accumulation of duplicate content, don’t worry. You can always use the canonical meta tag as an effective means to address the issue.
What is the canonical tag?
The canonical meta tag is placed in the HTML header of a web page. It tells search engines that the page is a copy of the URL indicated in the tag and that it should be treated as such. This prevents search engines from imposing penalties for duplicate content on your page because of the existence of said copies. This is the canonical tag:
<link rel=”canonical” href=”URL here” />
“Wait,” you say. “I don’t create duplicate content. I don’t need the canonical tag.”
Indeed. Any responsible website owner knows that creating duplicates is one of the easiest ways to drop out of the rankings. As such, many go to great lengths if only to ensure that every page is populated by unique content. Duplicates, however, do not necessarily have to be created by you. Here are some of the instances by which duplicate content may be created without your knowledge—or consent:
- The system may create session ID URLs in lieu of cookies or other URL trackers if they are disabled in your system.
- Different URL cases are usually redirected to the same location but at times, they may be recognised by search engines as duplicates of each other.
- E-commerce pages often make multiple URLs for the same page, especially if there are multiple available options for a single product. They also tend to usecountry-specific URLs to accommodate different currencies but these may be identified as duplicates of a single page.
- The mobile version of a page is also prone to getting mislabelled as a duplicate.
- Different mirrors of secured pages are often crawled separately and as such, may be read as duplicate content.
The canonical tag can be used to prevent these instances from having a detrimental impact on your website. While the process itself of applying the tag is straightforward, there are a number of ways that you can get it wrong.
- Do not have more than one canonical tag in a single page. A single canonical tag at the <head> section of every page is enough. Having more or putting the tag in the wrong place will lead the crawlers to ignore the tag(s).
- Do not use the canonical tag for multiple pages. In cases when you really must deal with multiple pages, you can use the prev and next tags instead of the canonical tag. You can also redirect crawlers to index a “View All” page instead. This page collates all the results together for easy review.
- Do not use your homepage as your preferred site. A canonical tag tells search engines to crawl the indicated URL instead of the page with the tag. Use this opportunity to have search engines reference the other pages in your site.
- Do not use canonical tags for featured content. There is a good chance that these pages will be ignored, making you lose some of the traffic for your features.
- Do not use 301 redirects and canonical tags interchangeably. While they do have similarities, 301 redirects are useful for when you have performed changes on your site’s structure. A 301 effectively redirects traffic, too. Canonical tags redirect crawlers, not traffic, and are great only for addressing duplicate content.
For all its apparent benefits, the canonical tag is effective only when you use it correctly. Keep in mind the proper mechanics before implementing it in your pages. You can look for strategies on the Internet on how you can use it or which other tags and techniques you can pair it with to give you better results.