Hyphens or Underscores? Who wins as best keyword separator in page names?
- Are hyphens better for separating keywords in your URI (Uniform Resource Indicator)?
- If so, why not separate words with an underscore?
NOTE: Many use the term URL (Universal Resource Locator), which has been deprecated. Old habits die hard. URI is the term for the portion of a Web page’s name after the domain.
Who wins as “Best Keyword Separator” is a contest SEOs and Webmasters want to know in order to optimize websites for search engines and for users. Understanding search algorithms is an ongoing game, for sure. Knowing what’s best for people (your audience) should be thrown into the ring to determine the winner.
![]()
The issue of hyphens or underscores in file names has been discussed and debated for years.
Does the hyphen, aka a “dash,” make any difference to the search engines?
More importantly…
Does a hyphen or an underscore make a difference to readers?
Vanessa Fox Answers Hyphens or Underscores Question
Vanessa Fox answered the following question by Leslie Youngstrom (@LeslieY on Twitter) for WebMasterRadio.fm Office Hours show on March 5, 2009:
@vanessafox Would love to hear a definitive answer on whether to use hyphens or underscores in filenames for best SEO. Research available?
The following is a truncated summary (not verbatim transcript) of Vanessa Fox’s gracious and sage answer:
If all else being equal, does Google not give extra weight for ranking for hyphens vs. urls.
What is in url does influence extra weight into the site. What is in your URL does influence the anchor text for linking. Also, a lot of people will click on links expecting to see content based on the keywords in the URL.
If someone is linking to you, when keywords are separated by hyphens, they are seen as distinct.
Underscores may be seen in a similar way. Google has said they are looking into it – that they will start looking at underscores the same as hyphens. But I doesn’t know for sure if they have implemented this.
The reason, originally, that underscores weren’t the same as hyphens is that Google was built by programmers. They thought of underscores as joining words.
Having keywords and hyphens in URLs is important from a user experience perspective. You want the highest click-through rates. If you have keywords in your URLs, you give people an indication of what they are going to see as they click through. Hyphens do a good job of separating words. Underscores are often not seen, and users wonder if it’s a space or an underscore, because links get underlined. Readers may not get the URL right. So from a usability perspective, use hyphens.
It’s the same amount of extra work to take two or three or four of the main keywords and put them in the URL. It doesn’t take extra work to put in the hyphens.
Studies have found people are more likely to click on a short URL. Go ahead and use hyphens.
Visit Vanessa Fox’s site for Office Hours podcasts. Once latest podcasts are posted, you’ll be able to listen to her answer.
Did you catch how Leslie phrased her question – “definitive answer” and “research available?”
Vanessa’s answer gave good reasoning for best practices. She provided insight about usability and what’s best for users. We all wish Google, Yahoo! and Live Search would answer DEFINITIVELY! Part of the answer may be subjective, however. I decided to see if there are any definite results or research.