Last week’s news that Google is now is treating underscores URLs as word separators, as it does with hyphens, quickly spread through the SEOs and webmaster communities. But what about the other search engines?
I immediately contacted them to find out how they treat underscores and hyphens. Finally, the results are in. Yahoo and Microsoft (and now also Ask.com), the other two of the big three, confirmed that they do treat underscores the same as dashes or hyphens in the URL.
Let me step back and explain this a bit more.
Some SEOs believe that the keywords in the URL of a page have some limited impact on the ranking of that page in the search engines. So if you sold blue widgets, and you had a page at www.domain.com/blue-widgets.html, those keywords are sometime perceived to help – while keeping all the other factors in ranking a page equal.
In the past, Google treated hyphens but not underscores in a URL as a word separator. So in our example above, the blue-widgets part would be seen as two different words: blue & widgets.
If it were like this, blue_widgets, then Google would have seen it as one single word: blue_widgets.
Now Google treats underscores the same way as hyphens. As for Microsoft, Ramez Naam told me:
We treat underscores as word separators in URLs. Always have.
Priyank Shanker Garg from Yahoo told me:
For URL tokenization (separating words in URLs), we treat dashes or underscores identically, but these are not our only tokens and we take a more general approach to finding words in URL.
I also asked Ask.com, but they’ve yet to send a reply.
Postscript: Peter Linsley of Ask.com has now given me a response, they treat underscores as word separators also.
For the record, we also treat underscores as word separators in URLs.
Postscript: We have an update from Google’s Matt Cutts that Actually, Dashes Aren’t The Same As Underscores Yet. We will keep you posted on this.