Rel canonical between mirrored domains

[AlexSG]

Hi all & happy new near!

I'm new to SEO and could do with a spot of advice:

I have a site that has several domains that mirror it (not good, I know...)  So www.site.com, www.site.edu.sg, www.othersite.com all serve up the same content.  I was planning to use rel="canonical" to avoid the duplication but I have a concern:

Currently several of these mirrors rank - one, the .com ranks #1 on local google search for some useful keywords. the .edu.sg also shows up as #9 for a dirrerent page. In some cases I have multiple mirrors showing up on a specific serp.

I would LIKE to rel canonical everything to the local edu.sg domain since this is most representative of the fact that the site is for a school in Singapore but...
-The .com is listed in DMOZ (this used to be important) and none of the volunteers there ever respoded to requests to update it to the .edu.sg
-The .com ranks higher than the com.sg page for non-local search so I am guessing google has some kind of algorithm to mark down obviosly local domains in other geographic locations

Any opinions on this? Should I rel canonical the .com to the .edu.sg or vice versa?

I appreciate any advice or opinion before I pull the trigger and end up shooting myself in the foot!

Best regards from Singapore!

[Dr-Pete]

I'm not sure there's a one-sized-fits-all answer. If the .com is more geared to an audience outside of Singapore, and the .edu.sg site is more geared to the local audience you could set a region and/or language with rel="alternate" hreflang:

https://support.google.com/webmasters/answer/189077?hl=en

This is a bit more subtle canonicalization signal that Google can use to sort out sites with language and/or regional copies (the regional aspect may be relevant even if both sites are in english).

The next question would be: where does your traffic come from? If you want to consolidate, but most of your traffic is coming from outside of Singapore, then I'd probably stick with the .com - it still has a "generic" status. The .edu.sg may rank more strongly in Singapore but fall off everywhere else.

I wouldn't worry much about the DMOZ link, especially if you have a solid link profile. DMOZ links have gotten buried over the years and typically don't carry nearly the value most people think. At some point, they could be a solid boost to a new site with a small link profile, but I think even those days are well behind us.

[AlexSG]

Fantastic response Dr. Peter! Thanks for taking the time to explain and to suggest the rel="alternate" tag which I have now implemented in a little experiment.

I very much enjoy your posts on the moz blog and thank you for all the indirect help they have given us in the past.

Best regards,

Alex

[Dr-Pete]

Happy to help - hope it does the trick.

[AlexSG]

Hi Dr. Peter,

Just thought I would share the initial results of your suggestion because they appear to be so dramatic!

I put it a rel=alternate tag on every page indicating the .edu.sg version of the URL for "en-sg" and the com version of the url for "en".

From MozAnalytics: Before
Rank 1-3: 4 keywords
Rank 4-10: 21 keywords
Rank 11-20: 3 keywords
Rank 21-50: 2 keywords
Rank 51+: 216 keywords

From MozAnalytics: After
Rank 1-3: 50 keywords!!!
Rank 4-10: 19 keywords
Rank 11-20: 3 keywords
Rank 21-50: 13 keywords
Rank 51+: 167 keywords

That's pretty crazy in under a week - Not sure if its 'real' since I never personally went to check rankings on these keywords, but wow! If the MozAnalytics information is correct I am blown away!   Unfortunately its for a niche site in a tiny market so its not going to lead to fame and riches, but its still an amazing result!

Thanks so much for the great advice

Alex

[Dr-Pete]

Wow - that's a huge impact. It's hard for me to believe this one change would have such an impact, but hopefully these new numbers stick.