If I permanently redirect (301) my old url.

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  Girish Kapoor: If i will permanently redirect (301) my old url with underscore (abc.com/about_us) to new url with hyphen (abc.com/about-us) then keyword ranking of this particular pages hurted or not.
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  Tony McCreath: No difference. Last I heard Google treat both as spaces.
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  Girish Kapoor: +Tony McCreath According to Matt Cutts this video hyphen is working as a separator and underscore is working as join, he is recommend if you are creating a new website then use hyphen, Underscores vs. dashes in URLs
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  Tony McCreath: +Girish Kapoor ;good spot. I shouldn't post without checking. They also recommend hyphens here ;https://support.google.com/webmasters/answer/76329?hl=en
  
  So the answer is the redirect may help, apart from the ranking leaked in the redirect!
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  Girish Kapoor: Thanks +Tony McCreath for your compliment but my question is keyword ranking is hurted or not....
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  Tony McCreath: A redirect causes a loss of PageRank which may affect ranking. I suspect its effect is more than the gain from switching characters.
  
  As Matt said, it's not worth changing old pages. ;
  
  I'd only do it if I was doing a major move, and fix underscores on the way.
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  Dave Elliott: nooooo. If he 301s it there should be no loss of rankings or any link bleed (i hate the term link juice so am trying to find a new description). And an underscore (so about_us) google will read as aboutus where as a hyphen(about-us) google will read as about us. ;
  
  What grish is proposing is as far as i'm concerned good practice and i can't see it harming anything.
  
  Although, this is a poor example, as you don't really want to rank for about us.
  
  http://searchengineland.com/google-pagerank-dilution-through-a-301-redirect-is-a-myth-149656
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  Girish Kapoor: Thanks +Dave Elliott i agree with you, but i am not asking only for about_us page. I am asking overall pages.
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  Tony McCreath: +Dave Elliott ;I have to argue about the 301 having no loss. That video I consider as a form of confuscasion or just something SEOs do not  ;understand. He said 301s have the same loss as a link. ;
  
  If you had a page with a single link in it. It would pass on the same PageRank as a 301 redirect. That means it suffers and adds to the same loss any link has. 5% or %15, who knows.
  
  A 301 is not as good as a direct link. And that is not taking into account crawl issues.
  
  I stick with my opinion that you should not cause redirects for cosmetic changes to a pages URL.
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  Dave Elliott: hmmmm from a very quick search it does seem you are correct. +Tony McCreath ;
  
  A 301 does cause a bit of bleeding. ;I thought it was less than 1%..... ok, I stand corrected.
  
  No point in doing it at all then, especially now exact match page names are becoming less of a ranking factor.
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  Girish Kapoor: +Jim Munro ; plz respond my query on today hangout
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  Edwin Jonk: From the expert panel in this weeks SEO Questions hangout on air on 00:19:23 into the YouTube video: https://dumbseoquestions.com/q/if_i_permanently_redirect_301_my_old_url +Girish Kapoor
  
  The cuetimes listed on this page are functional while the live broadcast continues and also once Youtube has finished processing the public broadcast. Processing time varies between 6-24 hours. During this period the clip is viewable in full but the cuetimes cannot be relied on. ;
  
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