This post has come due to a request from one of my readers at amp3pr.com. There is a lot of confusion about; when to use the nofollow attribute and when not to use it? Can it hurt your site? Will it enhance your SEO efforts or better optimise your site for Google?
These are all questions that are still flying around. To be fair there is only one person who can put an end to the debate and that is the big G, however I will try and add some clarity as well as adding a little of my own opinion, based on experience.
Google brought in the rel=nofollow attribute back in 2005 when comment spamming was reaching ridiculous levels (yes we have the spammers to thank again). The name “nofollow” suggests it is telling the search spiders to simply not follow the links, however what it is really saying is “do not use this link to pass PageRank” or to “not increase the value of the site the link points to”.
When it first arrived on the scene it seemed an excellent way to control comments and all other user generated content where the webmaster has very little control.
Google still do advocate using this attribute when you have “paid links on your site” however webmasters are using it on every single outbound link to prevent the leak of “PageRank” (which I personally believe is ridiculous and I’ll explain why later).
OK, I have mentioned the main reason for the over use of the “nofollow” comes down to the fallacy that you can leak PageRank, but first let’s understand how PageRank works.(If you didn’t know already)
Let’s start with the Google Definition.
“PageRank reflects our view of the importance of web pages by considering more than 500 million variables and 2 billion terms. Pages that we believe are important pages receive a higher PageRank and are more likely to appear at the top of the search results.
PageRank also considers the importance of each page that casts a vote, as votes from some pages are considered to have greater value, thus giving the linked page greater value. We have always taken a pragmatic approach to help improve search quality and create useful products, and our technology uses the collective intelligence of the web to determine a page’s importance.”
So in simple terms, PageRank is determined by the quality and quantity of votes (links) a particular page has pointing to it. Can we lose this PageRank? Do links out reduce the value of our links in? In my opinion NO
Understanding the Flow of PageRank
I am not going to go into the complex algorithmic equations that dictate how PageRank is calculated, what I want to do in really simple terms is allow you to understand what can hurt your PageRank and what is just a load of rubbish
Below is a simple example of a basic (small) link structure. The numbers represent the amount of PageRank passed, but don’t get hung up on how this is worked out, worry more about how it can be damaged.
So the aim here is to try and increase or maintain the amount of PageRank we have on our homepage.
Note: Each internal page is linked to from the homepage and each internal page links back to the homepage, therefore the homepage can pass and receive PageRank from internal or “sub” pages.
The important aspect that really needs clearing up here is this:-
No amount of outbound links from the “Home” page are going to reduce the 3.31 PageRank it HAS. Outbound links do not effect the page they are sent from (unless suspected as a link farm) however outbound links do have an effect on the amount of PageRank and link juice a page can PASS.
I hope I explained that well enough.
So (using the above image) if the homepage had 10 outbound links instead of 3. The amount of PageRank passed to those internal pages would be less as it is split between 10 pages now, not 3.
Can Outbound Links That Are Followed Really Hurt Then?
YES, they can. This is why it is good practice to use the nofollow but to use it wisely. Let me explain first the effect it can have.
Remember above I said the homepage (PageRank 3.31) was capable of passing PageRank to internal pages and was also capable of receiving PageRank from internal pages.
So the more outbound links you have on the homepage, the less PageRank will flow to the internal pages, therefore it is only natural that the internal pages will pass less back to the home page? Again using the above diagram;
- The homepage has a PageRank of 3.31
- This PageRank is calculated not only on the external links pointing to the homepage but also the internal pages that point to it.
- If the homepage has to share it’s juice between 7 more pages on top of the 3 it already has, it is only natural that less link juice will be passed to each page.
- Therefore any internal pages will have a lower PageRank and will pass a smaller amount back to the homepage.
- The end result is that the homepage decreases in PageRank as it has lost some of the link flow.
Does that make sense?
I hope so if anyone has any questions please feel free to contact me.
Let’s recap before moving on
- The nofollow was introduced to control outbound links
- People use it to stop the flow of PageRank
- Most believe that outbound links directly effect the PageRank of a page
Should We Use It or Not
Are you confused yet?
When it comes to using the nofollow attribute or not there is mixed feelings. As I mentioned earlier Google do recommend using it along side paid links, however many believe over use of it can raise search engine alarm bells. There is no concrete proof of this, there are stories of sites both increasing and decreasing in PageRank after optimising outbound links.
What I am going to try and do for you is give you a list of occasions when I would personally use the nofollow.
Directories and Widgets
Most of us have reciprocal links to directories of some sort, especially blogs. You can see a few of mine in my side bar. There are also certain widgets that we buy or place on our pages that have outbound links within
them. In my personal opinion there is no point in following them and Yes this includes your feedburner link (sorry feedburner as much as I love you, you hardly need help from me to increase your PageRank)
We all like outing unethical or let’s say questionable sites. We all should also know the importance of staying within a sound neighbourhood, therefore try to severe your association with suspect sites without simply not linking to it and warning your readers.
I also like to use it when linking to competition
SOME Internal Pages
The internal pages of your site that aren’t really important should also have the nofollow implemented. Matt Cutts and many others recommend this practice.
Apart from the above 3 I see no real reason not to follow any other links.
WARNING: Please don’t run off and implement nofollow on your site in MASS, this is sure to raise alarm bells. Do it in stages and that way you are keeping things safe.
I am sure there will be those of you with differing opinions and feel free to add anything in the comments.
I hope everyone now understands the nofollow debate a little better.
There is another debate which I may touch on another time which states “a nofollow link does not pass PageRank but MAY pass relevancy”…..hmmmm
Until next time
Author: Tim (292 Articles)
Tim Grice is the owner and editor of SEO wizz and has been involved in the search engine marketing industry for over 7 years. He has worked with multiple businesses across many verticals, creating and implementing search marketing strategies for companies in the UK, US and across Europe. Tim is also the Head of Search at Branded3, an SEO agency in Leeds.