Google: Canonical Tag Slower Than 301 Redirect

Dec 8, 2010 • 8:57 am | comments (11) by twitter Google+ | Filed Under Google Search Engine Optimization

googlebotGoogle's John Mueller said in a Google Webmaster Help thread that the canonical tag, used to inform search engines a URL has moved, is slower for Google to pick up on than if they used a 301 redirect.

John explained that Google would first have to crawl and index the first page to understand that there is a canonical tag on the page. Once they crawl it and understand the canonical tag, then they can add to their index that the page has moved.

If you used a 301 redirect, the spider would automatically be redirected from the original page to the new page, so there would be no indexing or crawling of the original page to determine if there is a canonical tag on that page.

This all makes logical sense, but I don't know if it was stated in black and white yet by Google.

John said:

When we initially crawl a URL, we'll generally index it with that URL first. A rel=canonical link element is not the same as a 301 redirect, so it will take more time for us to pick up on the final target, to crawl and to index that instead of the original URL. In general, that doesn't matter though - as long as the content is indexed, it'll be found, even with a "cid" attached.

He also added an important point for those who are doing mass usage of the canonical tag. He said:

If you are using this for canonicalization, keep in mind that we will still have to crawl all of those copies first, so depending on your site, that might be a significant load on your server (and it will slow down crawling and indexing of all of your content). If there's any way for you to remove session-ID parameters from internal links (assuming that's what the "cid" is), then that's something I'd strongly recommend working on. Having a site that is clear of unnecessary URL parameters will always make it easier to crawl and index.

So keep that in mind as well. It is not just slower for Google to pick up on but also may really impact your server resources, more so than a 301 redirect or making sure your site structure is solid.

Forum discussion at Google Webmaster Help.

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Simon Dodd

12/08/2010 05:17 pm

Awesome!! Thanks for that, duly noted and will be implemented for all my future page moving escapades! Another great post! Thanks, looking forward to the next one! Thanks Simon

Nathaniel Deal

12/08/2010 05:23 pm

Great post Barry, I've always treated them the same.


12/09/2010 09:10 am

Well explained! A canonical link element does have its uses but a 301 redirect is the way to if url has moved. It is nice to have it confirmed.

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12/09/2010 10:14 am

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Hyderali Shaikh

12/09/2010 12:33 pm

Are these Canonical only for dynamic sites? I've added this code "rel=canonical" in my static site but after three days even when the google crawls the site they didn't index the site with www but without www. So, after searching for the answers i've finally added 301 redirect which is now working perfectly.

Barry Schwartz

12/09/2010 12:34 pm

Works on any site or web page.


12/09/2010 10:53 pm

great i knew it but here is ovious google making mistakes and dont speak with honesty why do that? for me it is better to prevent and educate every one to be perfect, and not let him whithout knowing what he is doing no?

Dries Bultynck

12/10/2010 08:18 am

Clear and good answer! Tested it a few months back and like John says 301 is the best option. No doubt about it.


12/16/2010 06:52 am

Why is there even a choice? The 301 redirect works faster than something that wasn't even supposed to replace the 301 anyway. Anything running slower than normal means it's being used as directed. Do I smell more ?? I think I do.


12/31/2010 07:55 am

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01/01/2011 09:59 am

Absolutely a useful comment for my website designing. Kenneth

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