Search engines and canonical URLs

Multiple URLs can point to the same resource on a website, something that is especially common for a websites home page. That can cause some problems for search engines, since it may not be obvious to them which URL is the best to use.

In SEO advice: url canonicalization, Google employee Matt Cutts answers several questions related to canonical URLs, redirects, and multiple URLs. Much useful information here for anyone interested in making sure search engine robots have as little trouble as possible when they come to visit your site.

One of the topics is using the www subdomain or not in URLs. The key is to be consistent. Pick one and stick with it. However, since you have no control over inbound links and some of them will use www while others won't, it is a good idea to configure your server to redirect URLs the your preferred format. I do that here with a couple of rows in my .htaccess file:

  1. RewriteCond %{HTTP_HOST} ^456bereastreet\.com [NC]
  2. RewriteRule ^(.*) http://www.456bereastreet.com/$1 [R=301,L]

Any requests that do not use the www subdomain now get redirected to the same URL with "www" added in front of it.

Posted on January 12, 2006 in Quicklinks, Search Engine Optimisation