Search Engine Optimization (SEO) plays a significant role in your website’s overall visibility and performance. However, despite the best SEO practices, several factors can negatively impact your website’s rankings.
One major factor is canonicalization or canonical issues. In this comprehensive guide, let’s discuss everything you should know about these issues and how to tackle them to enhance your SEO performance.
What are canonical issues in SEO?
Canonical issues occur when multiple pages on a website point to identical or similar content. For instance, a website might load a similar page for all the following URLs:
Even if these URLs display the same page, search engines understand them as three independent pages or different content, causing a duplicate problem. This makes it difficult for search engines to find and rank your pages correctly, affecting your site’s visibility and resulting in lower search rankings and conversions.
Similarly, canonicalization issues can arise when your site has dynamic URLs. Dynamic URLs occur when a webpage dynamically generates content from a database.
UTM (Urchin Tracking Module) parameters can also cause canonicalization issues when not managed properly. For instance, UTM parameters appended to URLs create several versions of the same web page with divergent query strings. Furthermore, multiple URLs pointing to similar content with different UTM parameters can fragment your analytics data, making it challenging to represent traffic sources and user behavior clearly.
Why canonical issues cause problems in SEO?
Canonical issues confuse the search engines, causing a variety of issues that can negatively affect your website’s visibility and rankings. Some of the reasons you don’t want these issues on your website include:
- Duplicate content: Even if Google doesn’t penalize you for duplicate content, it can significantly harm your SEO performance. When you have duplicate pages, Google chooses and indexes one version of the page, excluding all the other versions from the search results. This might be a problem if the indexed page isn’t the one you would have preferred to rank. It can dilute your website’s authority, minimizing its likelihood of ranking high on search engines.
- Dilution of link equity: Backlinks are important for SEO since they pass trust and authority to the linked pages. Unfortunately, canonical issues can affect link equity since the linked pages point to different pages of the same content. For example, when identical content is available on multiple web pages, other sites may link to different URLs, diluting your traffic across multiple pages instead of concentrating on a single version.
- Keyword Dilution: When identical content is spread across multiple web pages with the same keywords, it leads to keyword cannibalization/dilution, making it hard for your primary pages to rank for specific target searches.
- Poor user experience: Having multiple URLs for the same context might cause confusion and doubts to your visitors. A user can land on different versions of the same content, increasing bounce rates. It also reduces the overall satisfaction of visitors to your website, prompting them to leave, which can dent your reputation and reduce your online presence and traffic.
- Inefficient crawl budget: Google engines assign limited resources and time to crawl and index a website. In cases where canonicalization issues create multiple identical pages, valuable resources are potentially wasted on indexing and re-indexing the same content repetitively. The engines may not crawl and index other useful content on your website, leading to missed SEO opportunities.
How to determine if your site has canonical problems?
Identifying canonicalization issues in your site is the key to resolving them. Below are common methods for detecting canonical problems:
- Manually Check URLs: In most cases, canonical problems are caused by HTTP/ HTTPS or WWW/non-WWW URLs. To check for these issues in your site, manually type and search for each possible version of your site’s URL. If all these URLs redirect to one of the URLs, then you don’t have a canonical issue on your site. However, if any URL doesn’t redirect to the preferred URL, you might have a canonicalization problem.
- SEO Tools: Popular SEO tools like Ahrefs, Moz, and SEMrush are helpful when checking for duplicate web pages and canonical problems on your site. These tools will review your website and produce a list of options that you can use to fix issues and enhance Google search optimization.
- Site Crawling: SEO tools like Screaming Frog and Sitebulb are valuable when checking for identical content and canonical issues on your website. While it might take some time to crawl your entire site, it’s an accurate way to uncover any hidden problems in your website and improve onsite visibility.
How to fix common canonical issues?
Typically, the right solution for your canonicalization issues will depend on the problem you’re looking to resolve. Possible options for fixing these issues include:
1. Use correct canonical tags
Instead of leaving it to Google to decide which page of the duplicate web pages to rank, you can specify the page you’d like to be considered as your canonical page by adding a canonical tag to its URL. A canonical tag (rel=”Canonical”) is an HTML code that helps search engines identify the preferred version of a URL.
2. Use self-referencing canonical tags
Having a self-referencing canonical tag on each page is a great way to mitigate the risk of canonicalization issues. These tags point toward themselves, signalling to the search engines which web page needs to be indexed.
3. Implement sitewide 301 redirects for duplicate pages
You can also solve canonical issues through 301 redirects. 301 redirects resolve problems arising from HTTP/HTTPS and WWW/non-WWW. This action redirects identical or similar pages to the chosen canonical URL. The search engines may rank this version and skip indexing the duplicate web pages. This ensures that all the traffic is directed to the original page.
Use the Google search bar to redirect a URL such as HTTP to HTTPS. Your hosting provider should be able to assist you with the redirection. Once you successfully redirect your URLs, the traffic and rankings for your website should improve within a couple of days. You can use AuthorityLabs to track your rankings.
4. Provide canonical tags to every page of your site
Adding a rel=canonical tag to every page on your website helps eliminate any possibility of duplication. Without the canonical tags, the Google search console might index multiple versions of your page on different URLs, resulting in duplicate content. Using the tags on every page of your site ensures that Google indexes the most valuable pages, improving your ranking and traffic. For WordPress sites, you can add canonical tags automatically using the Yoast SEO Plugin. From Advance tab, you will able to add Canonical URL for a particular page.
5. Redirect similar or duplicate pages to the selected url
If you’ve identified identical or similar pages on your site, you can redirect them to the chosen canonical link. For instance, if your site has a mobile and desktop version, you can select the site that will serve as your canonical version. The desktop page is often used as the canonical version.
Ensure that each page on the desktop page has self-referencing tags. Then, provide a canonical tag to each page that redirects the mobile site to a duplicate URL on the desktop page.
6. Fix canonical urls with Apache .htaccess files
The most common issue with canonical URLs is the www/non-WWW versions of the website. For example, https://www.yourdomain.com vs. https://yourdomain.com.
You can use Apache .htaccess files to eliminate identical pages and redirect search engines to the preferred canonical page. In this case, you have to decide the default version of your URL to use for better search ranking. Then, you should redirect all other URLs to the preferred or Canonical URL.
7. Make sure other sites use canonical tags when publishing your content
Sometimes other sites can use different URLs to site content on your website. To prevent canonicalization issues, request them to use canonical tags that direct to the original source.
Canonical Tags Best Practices
Keep in mind the following best practices when adding canonical tags to your site’s pages:
Use a canonical tag on every page of your website. Even if you don’t have duplicate issues, applying self-referencing tags to every page on your site helps eliminate any possibility of canonicalization issues in the future.
Ensure that other sites republish your content and add a canonical tag to your URL. Without this, Google might not know for sure which site is the primary source of the content. Google could end up ranking the republished page of your content higher than your page.
Use the same URL structure. Consider using the same URL structure for all your pages on your website. For instance, if the canonical version of your website is HTTPS or non-WWW, do not use canonical tags that use HTTP or WWW.
Use absolute URLs. To eliminate ambiguity, use absolute URLs in canonical tags, not relative ones. An absolute URL includes your domain and looks like https://www.yourdomain.com/page/, while a relative URL only contains the location following your domain, like /pricing/.
Check your canonical tags and web pages regularly. You can check your site for canonicalization issues occasionally using SEO tools like Ahrefs.
Don’t canonize if you can redirect. Since there’s no point in having identical content on different links, you only have to add a canonical tag to the primary page and then redirect the rest of the pages to the primary URL.
Canonicalize all pages in different languages to the main page for that language. For instance, if you have German and English versions of content on your site, canonized pages in German to the main page in German and English pages to the main page in English.
What are canonicalization attacks?
Canonicalization attacks happen when various inputs for the canonical name of a file or path are manipulated or substituted. For instance, an attacker can enter a file path in a URL, enabling them to access sensitive or unauthorized information on a website or web application.
What is an example of a canonical issue?
A common example of a canonical or canonicalization issue is when a website has different versions of URLs of the same page, say, HTTP and HTTPS. For instance, a web page can be available through different website links, like:
Unfortunately, Google considers these links as separate pages, causing duplicate problems. In such a situation, Google can index your website under these links, affecting your overall ranking and visibility.
Where Canonical Tags Should Be Used?
Canonical tags are essential for eliminating duplicate issues in websites. They indicate the preferred canonical version of a URL when there is identical or very similar content on a website. They signal the search engines to index and rank the primary page, enhancing your overall visibility.
Where Canonical Tags Shouldn’t be Used?
While canonical tags are very useful in eliminating canonicalization issues, there are situations where they shouldn’t be used, including:
- Pages with unique content: Canonical tags aren’t necessary if all the pages on your website have unique and distinct content. Using these tags in such a situation will only confuse the search engines and potentially affect your website performance.
- Cross-domain canonicals: Canonical tags are used to consolidate similar or identical content within the same website. Therefore, they shouldn’t be used to reference content on a different domain.
- No-index pages: Since canonical tags are used to indicate the preferred version of a URL that should be indexed, you don’t need to use them if you don’t want a page to be ranked in Google search.
Canonicalization issues can greatly affect your SEO performance by ranking multiple web pages of duplicate or similar pages of your website. Using canonical tags and other solutions explained above can help rank the right pages in your site, improving your ranking and overall performance. Also, be sure to regularly monitor your website for duplicate pages or URLs to eliminate any risks of canonicalization issues.