Since the age of dinosaurs, SEOs and their clients have been asking if they should put keywords in their URLs in order to improve visibility in search engines.
The short answer?
That wasn't very satisfying, was it?
Educated SEOs have known for some time that putting your keyword in the URL can help with your rankings, but some argue that the impact is miniscule and not really worth thinking about. Others say that it doesn't matter anymore, or even that it's bordering on "black hat." Still others think it's the greatest thing since sliced bread.
So, does putting a keyword in the URL matter enough for you to worry about it?
Read on to find out.
For Starters, They Definitely Matter
While the impact is debatable, there's no question that placing keywords in the URL helps. In 2009, Matt Cutts had this to say in a Google Webmasters Youtube video:
It does help a little bit to have keywords in the URL. It doesn't help so much that you should go stuffing a ton of keywords into your URL...If there's a convenient way that's good for users where you have 4 or 5 keywords, that might be worthwhile, but I wouldn't obsess about it to the level of, you know, how deep is the URL in the path, or, you know, how am I combining it...You don't need to make 7, 8, 10, 20 words, because that just looks spammy to users...
When Barry Schwartz asked him about the video, Cutts added "If you've got got an existing solution that works for you, it's not really worth going back to change your URLs. It may be worth considering when you're doing a new site."
In a 2010 YouTube video, Matt Cutts answered a question about whether you should put keywords in the URL path or the filename. He claimed that it doesn't matter from an SEO perspective, but nudged us in the direction of using more broad keywords as categories in the URL path, and more specific keywords within the filename itself.
Perhaps more interesting, though, is something Cutts muttered while he read the question. The question starts off by saying:
It seems that having relevant keywords in URLs is very helpful...[emphasis mine]
To which Matt Cutts muttered:
That same year, Google released an official "Search Engine Optimization Starter Guide." This is the only official SEO guide from Google, and the most recent one that was published. Take a look for yourself:
It's hard to argue with an official document released by Google in which Googlebot itself is telling us to "Choose a URL that will be easy for users and search engines to understand," and with an exclamation point no less.
How Much Do They Matter?
Don't get confused by correlation studies such as the one out of Search Metrics. This study tells us that having the keyword in the URL has a measly 0.01 correlation with rankings, but this is extremely misleading.
The same study says that having the keyword in the title has a 0.00 percent correlation with rankings, but we all know that placing the keyword in the title makes a huge difference. Don't confuse correlation and causation. The reason this correlation is so low is because if a page shows up on the front page of the search results, it almost always has a keyword in the title. You're not going to see an advantage just by looking at the search results, because the sites that didn't use the keyword in the title don't rank at all.
And so it goes with URLs.
Here's what happened when Garth O'Brien added keywords to the URLs for a movie review client:
Moving from a GUID URL structure to a keyword rich URL structure was the only SEO revision implemented in December of 2009. By the end of January 2010, FilmJabber realized a 30% increase in search engine referral traffic (we did compare year to year traffic and past January data). After 12 months FilmJabber witnessed an 130% increase of search referral traffic. Keep in mind Erik only implemented the new URL structure to six site sections of his website. [emphasis mine]
Crucially, he didn't make any other changes to the site in December.
The 130 percent increase in search traffic over the next year could be unrelated, but the only other thing that was going on was promotion via Twitter and Facebook, which has no direct impact on rankings.
Similarly, Brad Zomick of SkilledUp took a page from 221 clicks per day to 761 clicks per day, just by updating the title and URL for a page that was already ranking.
This Has Nothing to Do With EMD
Now, a clarification.
If you're thinking, "But didn't Google come out and say that keywords in the URL don't matter anymore?" this is actually a misconception. Google released something that has come to be called the EMD update back in 2012. This update eliminated some or all of the "edge" that entire domains had simply because they were named after a keyword.
Placing a keyword on the URL of a specific page is very different from buying an entire domain just because you think it might give you a slight edge in the search engines. EMD isn't and never really was SEO, it's "domaining." If you have to buy 1,000 domains to rank for 1,000 keywords, you're not doing SEO.
Is it Worth a Revamp?
While Matt Cutts says that you shouldn't revamp your whole site to fix the URLs "If you've got an existing solution that works for you," this isn't the kind of thing you should take at face value.
Revamping the entire site was definitely the right move when Garth O'Brien decided to do it, and it certainly seemed to work for Brad Zomick, but that doesn't mean it's always the right option, either.
The primary thing you need to keep in mind is that changing your URLs is literally changing your page. The links are pointing to the previous URL, not the new one. Redirects don't consistently transfer all of the link authority of one page to another. According to Matt Cutts, as of February 2013:
The amount of PageRank that dissipates through a 301 is currently identical to the amount of PageRank that dissipates through a link.
So a redirect doesn't tell search engines "this is actually the same page." It tells search engines, "act like this redirected page is linking to this new page."
This means that you would usually want to avoid changing the URL for pages that have a lot of inbound links. Pages with little or no inbound links, especially external ones, on the other hand, should be fine to change, and in fact will most likely benefit from the change.
The ideal solution, then, would be to change the URLs only for those pages on your site with limited ranking potential. The keywords in the URL should be more valuable than any link "dilution" that occurs from the redirect. That's especially true if you change all of your internal links so that they point to the new page, rather than the redirected one.
Ultimately, here's what it all comes down to. Putting keywords in the URL definitely helps if you do it right off the bat, and sometimes it's worth it even it means changing your URL structure. It's mainly a question of how to prioritize it, and whether any added benefit is better than the loss associated with a redirect.
The solution to that kind of prioritization is muddy, and I'd err on the side of caution. Don't change URLs for pages that have already accumulated a lot of links. Only change them for sections of your site that have little or no inbound link authority, and fix your internal links so they point to the new page, not the redirected one.