Matt Cutts, the go-to guy for all things Google, did a great interview with Eric Enge about – among other things – PageRank; and how it can affect your link building efforts if you use redirects too freely, bleeding away your hard one Link juice and associated PageRank.
(Page Rank Diagram)
Matt has commented heavily on PageRank before on his own blog:
(RE: sculpting) I wouldn’t recommend it, because it isn’t the most effective way to utilize your PageRank. In general, I would let PageRank flow freely within your site. The notion of “PageRank sculpting” has always been a second- or third-order recommendation for us. I would recommend the first-order things to pay attention to are 1) making great content that will attract links in the first place, and 2) choosing a site architecture that makes your site usable/crawlable for humans and search engines alike.
For example, it makes a much bigger difference to make sure that people (and bots) can reach the pages on your site by clicking links than it ever did to sculpt PageRank. If you run an e-commerce site, another example of good site architecture would be putting products front-and-center on your web site vs. burying them deep within your site so that visitors and search engines have to click on many links to get to your products.
There may be a miniscule number of pages (such as links to a shopping cart or to a login page) that I might add nofollow on, just because those pages are different for every user and they aren’t that helpful to show up in search engines. But in general, I wouldn’t recommend PageRank sculpting.
Now, Matt tackles PageRank and redirects with Enge:
Typically, the 301 Redirect would pass PageRank. It can be a very useful tool to migrate between pages on a site, or even migrate between sites. Lots of people use it, and it seems to work relatively well, as its effects go into place pretty quickly. I used it myself when I tried going from mattcutts.com to dullest.com, and that transition went perfectly well. My own testing has shown that it’s been pretty successful. In fact, if you do site:dullest.com right now, I don’t get any pages. All the pages have migrated from dullest.com over to mattcutts.com. At least for me, the 301 does work the way that I would expect it to. All the pages of interest make it over to the new site if you are doing a page by page migration, so it can be a powerful tool in your arsenal. (Matt later verified that a small amount of PR is lost through 301 redirects.)
What about 302 redirects? Matt says they are temporary, not intended to be permanent, and shouldn’t flow PageRank or link juice.
Bottom line? Have a reputable SEO firm help you correct links on your site and don’t depend on redirects unless you want to lose your link juice!
Tags: 301, 302, link juice, Matt Cutts, PageRank, redirects