Webmaster Preferred domain settings – WWW or Non-WWW
When you create a website it can be made accessible either through “http://www.urdomain.com” or “http://urdomain.com”, While this arrangement might be seemingly convenient – as visitors can type whichever version they prefer – but over the long term this may adversely affect your search engine rankings. And if you find your site is not being indexed, it means it might be indexed under a different domain. So if one needs to manage the domains in a better way, then you would have to use Webmaster Tools by registering first.
So to actually register in Webmaster Tools, one has to first verify the domains in Webmaster Tools for both www and non-www versions to ensure that you own both versions. If one of the version is verified it is very easy to verify the 2nd version as we can use the same verification method used for the 1st one. But if you have removed or deleted the file or meta tag or DNS record used for verification initially, you will have to repeat the whole verification method again for the 2nd one too.
Let us look on SEO point of view – Major search engines including Google deem the two versions as two distinct sites even if the contents are identical. Apart from other factors, search engine ranking also takes into account the number of incoming links to your site. If you retain both the versions some people may link to “http://www.urdomain.com” while some others may link to http://urdomain.com thereby splitting your back-link count.
Instead of perpetually being in doubt whether to opt for one or the other, it is prudent to you select one and permanently adhere to it. One simple solution to the complex problem is to set up a “301 Permanent Redirect” from any one version to the other once you decide on the preferred domain. This will enable search engines and visitors know which version is your preferred domain.
Once you decide finally on your preferred domain, that domain name will be used for all future crawls of your site and indexing refreshes. If no preferred domain is specified, then www and non-www versions of the domain will be treated as separate references to separate pages. There is a choice – you can redirect one version to the other using “301 permanent” redirects OR you can use the “canonical” tag to inform the search engines which version is the preferred one.
Setting a preferred domain will impact both crawling and indexing but you need to ensure that you own both versions. Webmasters however recommend using www.urdomain.com instead of“urdomain.com”.