Is there an SEO disadvantage to using responsive design instead of separate mobile URLs?

Matt's answer:

Today’s question comes from John E. in New York. John wants to know, “Does a site leveraging responsive design lose any SEO benefit compared to a more traditional m. Site?” OK. So let’s explain exactly what’s going on here. Whenever you have a site that can work well for regular browsers on the desktop as well as mobile phones, there’s a couple completely valid ways to do it. One is called responsive design. And responsive design just means that the page works totally fine whether you access that URL with a desktop browser or whether you access that URL with a mobile browser. Things will rescale, the page size will be taken into account, and everything works fine. Another way to do it is, depending on the user agent that’s coming, you could do a redirect, so that a mobile phone, mobile smartphone, for example, might get redirected to a mobile dot version of your page. And that’s totally fine as well. We have guidelines and best practices that we’ll include in the description of this video how to do that and handle it well. Things like having a rel=canonical from the mobile version to the desktop version, that sort of thing. In general, I wouldn’t worry about a site that uses responsive design losing SEO benefit, because by definition, you’ve got the same URL. So in theory, if you do a mobile version of your site, if you don’t handle that well and you don’t do the rel=canonical and all those sorts of things, you might in theory divide the page rank between those two pages. But if you’ve got responsive design, everything is handled from one URL. And so the page rank doesn’t get divided. Everything works fine. So you don’t need to worry about the SEO drawbacks of responsive design at all. You need to make sure that your page works well for users and that it’s fast and all that sort of good stuff. But I wouldn’t worry at all about responsive design and whether that will hurt you in terms of SEO.

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

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