How does URL structure affect PageRank?

Matt's answer:

Here’s a fun question from Chris F. Masse, who asks, “On your WordPress.org blog (mattcutts.com), why did you switch from domainname.com/year/ month/day/sample-post/ to domainname.com/postname/? Has this to do with how PageRank flows within a site?” Okay, so this seems like a very insider kind of question, but let’s try to pull something that people would be interested in. I don’t think that I ever did year/month/day/. I can–I can see the argument both ways because it’s really handy to users if they land on a page and very easily they can see, “Oh, this article is four years old. I’m gonna, you know, look for the newer version of this article.” And at the same time, it makes the URL a little bit uglier, because if you can just land on mattcutts.com/googlechrome or something like that, that’s very easy for them to remember, and it’s a very simple URL. So I’ve always used just postname. I can see the arguments both ways. Um, but let’s tackle your second part of the question. “Has this to do with how PageRank flows within a site?” So Google, historically, doesn’t worry so much about how deep a set of directories is. So if you had your root page, and you linked directly to a very deep page, that page would still get the PageRank from the root page. And other search engines might do it differently. In fact, I wouldn’t be surprised if Yahoo! or Bing looked at how many directory tree levels there were, but, historically, Google doesn’t really worry about that very much for just sort of general Web searches. So if I did make that–if I, you know–I didn’t make that change, but it would be fine to have year/month/day/ in terms of the PageRank would still flow within the site just fine based on links. We tend not to worry about, okay, how many directory tree levels there are. Um, which way to organize it? It’s kinda up to you. I’ve gone with the simple thing of just the postname.

by Matt Cutts - Google's Head of Search Quality Team

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