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Canonical Issues

Solve duplicate content signals.

A canonical issue, also known as a canonicalization issue, refers to a situation where multiple URLs are used to access the same or similar content on a website. It occurs when different URLs lead to identical or highly similar web pages, resulting in duplicate content signaling related to search engine optimization (SEO) and adverse content indexing.

Canonical issues can arise due to these five reasons:

  1. WWW vs. non-WWW versions
    Websites can be accessed using both the “www” and “non-www” versions of the URL. For example, “” and “” may point to the same content. This creates a duplication issue in search engine indexes.
  2. HTTP vs. HTTPS
    Websites may have both HTTP and HTTPS versions accessible. URLs starting with “http://” and “https://” can lead to the same content, leading to duplication problems.
  3. Trailing Slashes
    URLs with or without trailing slashes often display the same content. For instance, “” and “” could serve identical content.
  4. URL Parameters
    Websites that use URL parameters to generate different versions of the same content can encounter canonical issues. For instance, “” and “” may produce duplicate content issues.
  5. URL Case Sensitivity
    URLs may be case-sensitive or case-insensitive. This may produce duplicate content issues when the same content is accessible via URLs with different capitalization.

Canonical issues can impact technical SEO because search engines may view duplicate content as a signal of low-quality or manipulative practices. This can lead to a decrease in search rankings, as search engines determine which version of the content is the most relevant.

To avoid canonical issues, implement a canonicalization strategy that specifies the preferred version of your URL to search engines. This is often accomplished by adding a canonical tag, which is an HTML element placed in the head section of a web page. The canonical tag indicates the preferred URL version, helping search engines avoid indexing duplicate content.

By resolving canonical issues and establishing a consistent and preferred URL structure, you can enhance your technical SEO efforts, improve search engine rankings, and ensure that content is properly indexed and attributed to the desired URL.