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What is Canonicalization


Canonicalization (canonization) is a process by which a particular format, whether it is a document, a URL or other type of data is converted to a previously agreed format. Canonicalization can be used to correct formatting errors and prevent a single URL is displayed more than once.


The main advantage of Canonicalization is that it allows users to work more quickly and efficiently with a document or a URL to deal with. It also facilitates the recognition of a single document or a URLso that they are not displayed more than once or the processing of a single document or a URL can be simplified.


A disadvantage of Canonicalization is that it refers to a specific format, so not all documents or URLs can be converted. This means that some documents or URLs may not be converted, leading to possible errors and conflicts.

Use cases

Canonicalization can be used in many different use cases, including correcting errors in the formatting of documents and URLs, preventing URLs from being displayed multiple times, and simplifying the processing of individual documents or URLs.


An example of the use of Canonicalization is when a website offers multiple URLs for the same page. These URLs can be identified with the help of Canonicalization so that they all point to the same page. Another example is the use of Canonicalization when processing documents. If a document is available in several different formats, it can be edited using the Canonicalization converted into a uniform format.


Canonicalization can be a very useful tool to correct errors in formatting of documents and URLs and to prevent multiple display of URLs. It can also be used to simplify the processing of individual documents or URLs. While Canonicalization may be convenient, it may also prevent some documents or URLs from being converted, possibly leading to errors and conflicts.

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Q1: What is Canonicalization? arrow icon in accordion
A1: Canonicalization is a process of making the same meaning of a value in multiple formats (e.g., different URLs) conform to a consistent format. Canonicalization can ensure that all URLs on a website are standardized to the same format to avoid duplicate content and improve search engine optimization.
Q2: Why is Canonicalization used? arrow icon in accordion
A2: Canonicalization is used to ensure that different URLs point to the same website. This ensures that there is no duplicate content on websites, which improves search engine optimization.
Q3: What are the types of canonicalization? arrow icon in accordion
A3: There are basically two types of canonicalization - vicarious and explicit canonicalization. In the case of vicarious canonicalization, a single URL is used as the default for all others, while in explicit canonicalization, each URL is specified individually.
Q4: What are the benefits of canonicalization? arrow icon in accordion
A4: Canonicalization can provide several benefits, including better search engine optimization, a reduction in load times, and an improved user experience. It helps avoid duplicate content by ensuring that all URLs point to a single website.
Q5: How to implement Canonicalization on a website? arrow icon in accordion
A5: Canonicalization can be implemented in several ways, depending on the type of canonicalization to be used. This can be done either by using a website framework or by manually editing the source code.
Q6: How is canonicalization different from redirects? arrow icon in accordion
A6: Canonicalization is used to standardize multiple URLs to a single URL, while redirects are used to redirect a request from one URL to another. Both techniques have their own benefits, but canonicalization can do more to avoid duplicate content.
Q7: Why is Canonicalization important for SEO? arrow icon in accordion
A7: Canonicalization is important for SEO because search engines reject duplicate content and result in poorer search engine optimization. Canonicalization allows website owners to ensure that search engines treat all URLs on a website as a single piece of content and rank the content as unique.
Q8: Are there any disadvantages of canonicalization? arrow icon in accordion
A8: Canonicalization can result in some content not being indexed properly, as search engines only display a single version of a piece of content. Therefore, website owners must ensure that the canonicalized URLs are the correct ones and contain all relevant content.
Q9: How is canonicalization verified by search engines? arrow icon in accordion
A9: Search engines verify canonicalization by checking the header of the document (e.g. the link tag) to see which version of the URL is specified as canonicalized. They also use other techniques to ensure that canonicalization has been implemented correctly.
Q10: How can you ensure that canonicalization is implemented correctly? arrow icon in accordion
A10: To ensure that canonicalization is implemented correctly, website operators must make sure that the canonicalized URLs are the correct ones and contain all relevant content. They should also check that the canonicalization code has been implemented correctly on all pages and regularly check that it is still up-to-date to avoid problems with search engines.

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