How To Use No Follow

Do follow vs no follow tags?

Once upon a time the concept of No-Follow was a simple one. Matt Cutts has finally come out with some clarifications on a change that was implemented in 2008.

You see the pages on a website have PageRank (an measure of incoming link authority), the more PageRank the better your rankings in Google will be. The PageRank of a page gets past on to all the pages it links to (external and internal). This resulted in a lot of abuse as people commented on blogs purely to get a back link and steal some juice, or publicly bookmarked there own pages to get some link-juice from those sites.

To combat this a No-Follow tag could be added to your links - the original idea was that it would block up those holes in your page and not pass on the valuable PageRank - leaving you to direct and sculpt it where you want it to go! ( rel=nofollow).

Lists of Do Follow Social Bookmarking Sites became a valuable resource.

Note: There is no ‘Do Follow’ tag is simply a term coined to describe a link that does not have a NoFollow tag present.

But No-Follow soon became overused, and there was much speculation as to whether it was still working or not.

Pre 2008: The PageRank was only dived up amongst the do follow links.
Post 2008: The PageRank is divided up amongst all outgoing links, but only passed through to Do Follow links.

This clarification comes right from the horse’s mouth » Matt Cutts (Google) talking on No Follow / Do Follow - June 15th 2009

• The PageRank of a page is split amongst the outward links.
• The PageRank decays each time it gets passed on.
• No-Follow links do NOT pass PageRank or Anchor Text.
• No-Follow links DO count when dividing up the % of page rank passed.

Matt Cutts Advice on How To Use No Follow:

1. Make great content worth linking to.
2. Choose a site architecture that’s usable for humans and crawlable for search engines.
3. PageRank sculpting is not recommended.
4. A better form of PageRank sculpting is to choose which things to link to from your home page and main folders.
5. When you are linking within your own site, do not use no follow tags.
6. Don’t close your comments in an attempt to hoard your PageRank.
7. Linking to good sites is still valuable (screen your do-follow outgoing links), other parts of the Google system encourage and reward these links.
8. Let PageRank flow freely throughout your site.
9. Nofollow links, DO NOT help sites rank higher in Google’s search engine.
10. Use nofollow on comments or when you can’t or don’t want to check the quality of the site linked to.
11. Letting PageRank flow within your websites will result in more pages appearing in the search engines.
12. Don’t try and force your way to the top of Google , before everyone has found all the great content on your site.
13. If you truly DO NOT want to pass PageRank  to another site use a nofollow tag on the link.

In the old system, all of the PageRank went through to the Do Follow links. That still happens but now the number of No Follow links plays a part in weakening the PageRank passed on through the Do Follows.

The ultimate truth is that Google decides on the amount of PageRank that passes through every link and the no follow is the blocker that allows you to prevent a link from getting its allocated PageRank.

PageRank sculpting will still happen as people attempt to conserve PageRank rank by limiting the amount of no follow and do follow links on a page.

The final question… Where does all the left over PageRank go?
In the visual representation I created for you, we start with 100%, ~10% gets lost in decay, but due to the 2008 changes only 45% gets passed on. Lets just say I had a page with a PageRank of 10. A total PageRank of 4.5 gets passed on through my (internal and external) outgoing links, so what happens to my other 5.5 PageRank? The implication (as it’s not clear) seems to be that it does not evaporate but returns to the page.