HostMonster Web Hosting Help

Canonical URLs: Telling Search Engines which to Use

‚Äč

For any given website page, there are more than one URL that can be used to get to it. While this is extremely useful in certain situations, like when you want to view your page before the domain propagates, it sometimes can cause undesired effects.

Luckily most search engines, like Google & Bing, understand every page has multiple working URLs, so they usually correctly determine what pages are duplicates, and what URL is most likely the canonical URL. The canonical URL is the preferred URL for a page.

Examples of URLs for a Single Page

For example, depending on your setup, it may be possible to visit the same page by using the following example URLs:

  • primarydomain.com
  • www.primarydomain.com
  • 10.0.0.2/~username/
  • primarydomain.com/index.php
  • www.primarydomain.com/index.php
  • 10.0.0.2/~username/index.php

If the domain is an addon domain, it may be possible to view the same page through these hypothetical URLs:

  • addondomain.com
  • www.addondomain.com
  • primarydomain.com/addondomain.com
  • addondomain.primarydomain.com
  • 10.0.0.2/~username/addondomain.com
  • addondomain.com/index.php
  • www.addondomain.com/index.php
  • primarydomain.com/addondomain.com/index.php
  • addondomain.primarydomain.com/index.php
  • 10.0.0.2/~username/addondomain.com/index.php

How Search Engines Guess the Canonical (Preferred) URL

First of all, it is important to note that even though all of the URLs exist for the same file, most search engines and your visitors will never encounter them and will not even know they exist. So, for example, that temporary URL your host gave you with your IP address and username in it will only be known by you, unless you tell someone else about it.

Of the ones it knows about, they only know it exists because someone told them about it, usually by using it in a link on a web page somewhere.

Search Engines usually find URLs a couple of ways:

  • They found a link to your page on a web page they already knew existed.
  • The found the link / URL in a site map and/or RSS feed.
  • The link / URL was submitted to them directly, usually via their website.
  • Somone visited your page while using their browser toolbar.

Once they find out about the page, they compare it will other pages that appear to be identical or almost exact matches to spot duplicates. If they spot a duplicate page, they then try to figure out which URL should be the canonical URL.

Although they keep their exact algorithms secret, there are some things that they are known to check:

  • What URL everybody seems to be using when linking to you.
  • What URL is used in your site map and RSS feeds.
  • Whether you specified a canonical URL in the meta tags of your pages.
  • For Google, whether you specified a canonical URL in Google Webmaster Tools.
  • Whether the URL redirects to another URL.

Resouces:

Here are some useful resouces from Google and Bing:

Knowledgebase Article 4,717 views bookmark tags: (updated 427 days ago)


Was this resource helpful?

Did this resolve your issue?


Please add any other comments or suggestions about this content:





Recommended Help Content

Why doesn't my domain name show up in search engines? (updated 1633 days ago)
Knowledgebase Article 46,247 views tags: engine promo promote search

Why is my site not the first result on Google or an other search engine? (updated 974 days ago)
Knowledgebase Article 42,985 views tags: bing engine google search seo yahoo

How does Search Engine Placement work? (updated 1652 days ago)
Knowledgebase Article 62,457 views tags: engine promo promote search

Related Help Content

Why will Entropy not search any php file? (updated 1634 days ago)
Knowledgebase Article 50,700 views tags: php search

I am trying to rebuild my index for Entropy Search and it stops before 100%. (updated 1654 days ago)
Knowledgebase Article 49,194 views tags: index search

A guide on adding a search bar to your Basekit site. (updated 462 days ago)
Knowledgebase Article 3,066 views tags:

A guide to configuring google's crawl rate for your site. (updated 442 days ago)
Knowledgebase Article 25,448 views tags: google seo

A guide to configuring bing's crawl rate for your site. (updated 447 days ago)
Knowledgebase Article 23,393 views tags: bing seo

Step by step directions on how you can search your database using phpMyAdmin (updated 454 days ago)
Knowledgebase Article 5,441 views tags: Plesk cpanel databases mysql phpmyadmin

How to remove the "This site may harm your computer" warning in Google search results. (updated 799 days ago)
Knowledgebase Article 145,462 views tags: block blocking google malware

Explains the use of DirectoryIndex and how to use it. (updated 442 days ago)
Knowledgebase Article 8,230 views tags: cpanel htaccess