Using the noindex tag can be tricky if you don’t know what you’re doing. With the noindex tag, by inserting this meta tag into the HTML code of a web page, you can prevent a page from appearing in the Google search results entirely, regardless of the number of links that are connected to it.
The noindex tag can be quite a wonderful thing, if you use it correctly. But there can be times when including the noindex tag in your page’s HTML code can do more harm than good.
There has been a number of websites that Eric Enge has worked on that includes hundreds of millions pages. There are many reasons why a webmaster would allow a site to get that big, but when this does happen, this means that many of the pages have very little redeeming value to them, or the difference between them are barely noticeable.
As an example, lets say you have a site that is selling shoes, and one page is selling size 11 black Nike’s and another page that is selling size 11 grey Nike’s. Sure, you could say that this slight difference in shoe color would make sense when it comes to having two separate pages, but does the insignificant difference really require the addition of a second page?
Having separate pages might make sense in your mind, but to Google, it isn’t so. Having pages like this is that your site can be flagged by Google as thin content. The result of this could mean either a loss of visibility due to the Panda algorithm, or worse, a manual penalty.
There is an option though. You could always use the noindex tag on the pages you don’t want to be included in Google’s index. By doing this, you can get rid of the risk of the manual penalty or being hit by Panda. But this isn’t always the best course of action.
In an article on Search Engine Land, Eric discusses the common issues that will arise from improper implementation of the noindex tag. Do you want to know when it’s a good idea to use the noindex tag, and when it is? Check out Eric’s post now!
Search Engine Land: SEO Nightmare: When NoIndex Goes Bad