Canonical Links

What is a canonical URL

The attribute <link rel = “canonical” /> allows you to specify a canonical search robot, that is, the main version of the document. This attribute will need to mark not only the main page of the Internet project being promoted, but also its duplicates. If the robot finds copies of the canonical page on the site, it will mark them as insignificant. The canonical URL is the easiest method of dealing with duplicate content.

How canonical link works

Suppose we have a main page http://yoursite.com/statya1 , which can also be found at several addresses:

http://yoursite.com/page?id=5

http://yoursite.com/blog/statya1

To indicate a canonical page to a search engine, add the following line to the code of each of the above documents:

This code snippet should be placed between the <head> </ head> tags. This will increase the chances that the main document will be displayed in the results of the issue, but not its duplicates. It should be noted that the rel = “canonical” attribute is taken into account by most modern search engines.

Why CMS create doubles:

No need to assume that the content management system intentionally generates duplicate pages. Usually such copies are created due to incorrect CMS settings. The most common reasons for duplicates include:

1. creating archives from old articles;

2. Availability of open links to documents in the PDF version (for printing);

3. wrong site structure, adding identical pages in different categories;

4. The presence of dynamic URLs (typical for online stores).

To identify duplicate pages and use the rel canonical attribute, you can use Google’s tools for webmasters. You need to go to the tab “view in search” and click on the link “Html optimization”. In the section that opens, there are pages with repeated meta descriptions. Such documents often have duplicate content.

Recommendations for canonical links

PS Google advises not to specify the attribute rel = “canonical” as a directive for robots.txt. This can cause problems with site indexing. You cannot specify different canonical URLs for one page (for example, one URL in the site map and the other directly in the <head> section of the page).

To reduce the likelihood of error when indexing a site, absolute and not relative paths should be specified as the link rel attribute. In other words, instead of the structure / blog / page-1 you should use the full address http: // yoursite / blog / page-1.