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Quick SEO Fix: Set Your Preferred Domain (Or, URL Canonicalization)

 In SEO, Technical SEO

Say your Web site domain is “” If a user enters “” or “” without the “www,” do both work as is? If so, you have a problem.

I’ll explain. It’s common to see a list like this, as all the same urls:
• /

In fact, these are all different URLs, each potentially pointing to a unique page or site. A Web server could server completely different pages and content for each of these, so a search engine has no way of knowing that they are meant to be a single site. Therefore, each will accrue SEO rankings independently of each other, and you will not get the total value of inbound links to your site.

What is Canonicalization and How Do I Do it?

Canonicalization is the process of picking the best URL when there are several choices. The alternatives should not work on their won – they should all be re-directed to the same preferred URL.

Matt Cutts of Google recommends a few approaches to canonicalization to help indicate which URL is preferred.

First, pick the form of the URL you like. I recommend that you leave off anything after the slash itself – no “index.html” or “default.html,” etc… stick with the domain and end with a “/” (forward slash). The forward slash technically indicates a folder or directory, rather than a single page. So it’s proper form, for example, for the home page of your site. And “www” vs. no “www” is a matter of taste, and what people may be used to.

Now that you’ve selected one, stick to the preferred domain in every situation. Do not give some people one version and other people another. Be sure your email signature, your Web site, blog, email newsletter, paper newsletters, promo pens, business cards, and all else, always use the selected format. Insist on this internally.

Redirect all the other URLs to the selected format. Use a permanent redirect (also known as a 301 redirect), to redirect all these other forms that you know are out there, to your newly selected “canonical URL.” So if you’ve decide to go with “” and someone clicks on, or types in “,” it will resolve to ““” — Be sure you also redirect “” to “” with the slash.

Use Google Webmaster Tools – Login to GWT (Google Webmaster Tools), a free set of terrific tools from Google for SEO and related monitoring of your site. In GWT you can tell Google which is the preferred domain. When creating a GWT account you need to verify that you own the domain. There are a few easy ways to do that, and you will need to verify ownership for both versions when you set the preferred domain. There are similar functions available for both Yahoo! and Bing.

As I mentioned, URL canonicalization, or setting a single preferred domain, is a very common omission, easy to fix, and very costly if you don’t. It’s definitely low-hanging SEO fruit which you should pick now, if you haven’t already. This is big bang for the SEO buck.

Let us know if you’d like help setting up Google Webmaster Tools for your Web site or with setting your preferred domain in general. Then let us know what kind of impact you see on your rankings!

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