Canonical and Alternate Advice

JH_OffLimits

At the moment for most of our sites, we have both a desktop and mobile version of our sites. They both show the same content and use the same URL structure as each other. The server determines whether if you're visiting from either device and displays the relevant version of the site.

We are in a predicament of how to properly use the canonical and alternate rel tags. Currently we have a canonical on mobile and alternate on desktop, both of which have the same URL because both mobile and desktop use the same as explained in the first paragraph.

Would the way of us doing it at the moment be correct?

Nigel_Carr

Hi JH

This is very straightforward.

Use the following annotations:

On the desktop page, add a rel=”alternate” tag pointing to the corresponding mobile URL. This helps Googlebot discover the location of your site’s mobile pages.
On the mobile page, add a link rel=”canonical” tag pointing to the corresponding desktop URL.

It is that simple and doing this will not create duplicate content

More here: https://developers.google.com/search/mobile-sites/mobile-seo/separate-urls

Regards Nigel

effectdigital

The problem with this is, where you say "corresponding mobile URL" - there isn't one as OP has stated that, two different source codes (pages) can be rendered on the same URL depending upon the user's screen size / user-agent (however they are detecting mobile, and serving different pages)

effectdigital

Your problem is that you have two different sites loading on the same URL. If you are returning both the mobile and desktop / laptop site on the same URL, you would be expected to be using responsive design. In-fact, you may have re-invented another different way to implement responsive design which is probably, slightly less fluid yet slightly more efficient :')

Since your mobile and desktop pages both reside on exactly the same URL, I'd test the page(s) with this tool (the mobile friendly tool) and this tool (the page-speed insights tool). If Google correctly views your site as mobile friendly, and if within PageSpeed insights Google is correctly differentiating between the mobile and desktop site versions (check the mobile and desktop tabs) then both URLs should canonical to themselves (self referencing canonical) and no alternate tag should be used or deployed. Google will misread the alternate tag, which points to itself - as an error. That tag is to be used when your separate mobile site (page) exists on a separate URL, like an 'm.' subdomain or something like that

Imagine you are Googlebot. You are crawling in desktop mode, load the desktop URL version and find that the page says, it (itself) is also the mobile page. You'd get really confused

Check to see whether your implementation is even supported by Google using the tools I linked you to. If it is, then just use self referencing canonical tags and do not deploy alternate tags (which would make no sense, since both versions of the site are on the same URL). When people build responsive sites (same source code on the same URL, but it's adaptive CSS which re-organises the contents of the page based upon viewport widths) - they don't use alternate tags, only canonicals

Since your situation is more similar to responsive design (from a crawling perspective) than it is to separate mobile site design, drop the alt

Nigel_Carr

Then there is no problem simply putting a self-referencing canonical. There is in effect no mobile version as there is a single URL so no need for a rel=alternate.

It's an even easier solution. Well, there isn't a problem in the first place.

rel=alternate is only necessary if you have two different URLs! The fact they are the same takes away the problem.

Regards

Nigel

effectdigital

The self referencing canonical advice was solid and I 100% agree with it. The rel=alternate advice, I felt would cause problems (IMO). But as we all know, fiddly issues like this are highly subjective

Nigel_Carr

You are right - you could only use teh rel=alternate if there was an m. version or similar

Regards

Nigel

JH_OffLimits

Would this mean we need canonical only on desktop or mobile site?

BlueprintMarketing

You guys are fast I was going to answer this and had to do some other things but let me weigh in on couple things.

as you said

“We are in a predicament of how to properly use the canonical and alternate rel tags**. Currently we have a canonical on mobile and alternate on desktop, both of which have the same URL because both mobile and desktop use the same as explained in the first paragraph.”**

so what you’re saying is that you have a dynamic site so you don’t need to add “alternate"media” tags to the site.

https://developers.google.com/search/mobile-sites/mobile-seo/dynamic-serving

As it is not immediately apparent in this setup that the site alters the HTML for mobile user agents (the mobile content is "hidden" when crawled with a desktop user agent), it’s recommend that the server send a hint to request that Googlebot for smartphones also crawl the page, and thus discover the mobile content. This hint is implemented using the Vary HTTP header.

you don’t need this

Annotations in the HTML

On the desktop page (http://www.example.com/page-1), add the following annotation:

<code dir="ltr"><linkrel="alternate"media="only screen="" and="" (max-width:="" 640px)"<br="">href="http://m.example.com/page-1"></linkrel="alternate"media="only></code>

On the mobile page (http://m.example.com/page-1), the required annotation should be:

 <code dir="ltr"><linkrel="canonical"href="http: www.example.com="" page-1"=""></linkrel="canonical"href="http:></code>

This rel="canonical" tag on the mobile URL pointing to the desktop page is required.

Annotations in sitemaps

We support including the rel="alternate"annotation for the desktop pages in sitemaps like this:

 <code dir="ltr"><urlsetxmlns="http: www.sitemaps.org="" schemas="" sitemap="" 0.9"<br="">xmlns:xhtml="http://www.w3.org/1999/xhtml">
  <url><loc>http://www.example.com/page-1/</loc>
    <xhtml:linkrel="alternate"media="only screen="" and="" (max-width:="" 640px)"<br="">href="http://m.example.com/page-1"/></xhtml:linkrel="alternate"media="only></url></urlsetxmlns="http:></code>

The required rel="canonical" tag on the mobile URL should still be added to the mobile page's HTML.

**to be sure **

Are you willing to share your domain with us? Or one domain?

We're talking about multiple websites that all have the identical site structure or at least mobile and desktop site structure?
Your server is making the change for you?
Would you be kind enough to install this plug-in on chrome in order for you to show a couple examples of the canonical and the URL?

In addition, would you be kind enough to run your site through the two tools here ( 100% free and very easy to use)

If you would not mind doing this and sending screenshots it would mean a lot to us and getting your canonical's straightened out.

screenshots https://snag.gy/ then upload to http://imgur.com/

everything is on the same server I'm assuming?

Of the three below how would you categorize your site?

Respectfully,

Tom

Nigel_Carr

The URLs are identical it is just the content that is served that may be slightly different.

Since you can only specify one canonical for each URL it makes no difference. Just self-reference and that is it.

If you had to different URLs then it would be an issue where you woudl need a rel=alternative so there is nothing to worry about.

Regards

Nigel

effectdigital

This is the correct solution!

JH_OffLimits

Hi,

I can't give off too much information as it's not my call, but I can answer your questions without mentioning the brands.

1. We have multiple brand sites, that have a similar setup. They all have mobile and desktop versions of the sites running on the same URL, both of which show the same content.

2. The server determines whether if you're on a desktop or mobile devices using the header information, and points the user to the site relevant files for the given device.

3. Our sites would quite clearly fit in the dynamic serving category.

We have 301 redirects on none www to www and http to https.

BlueprintMarketing

Cool, that's what I thought when I heard your description I just wanted to be very thorough because sometimes you get very little information and I appreciate you letting me know that.

dynamic serving URLs are identical to each other so you should have a self-referencing canonical tag because the URL does not change the real canonical tag just decides what should be in the index and the same URL.

You're Rel canonical should be something like this example below

Example URL https://www.example.com/example-url/

because the end URL is the same and URL that you want to be indexed in Google you want to be certain that you have a self-referencing URL to prevent query strings and other things like that and you do not need to point a URL to an identical URL you just need a self-referencing canonical if that makes sense.

See: https://yoast.com/rel-canonical/

I hope that is of help,

Tom

BlueprintMarketing

Unless you are using AMP?

Then you would add

Linking pages with

In order to solve this problem, we add information about the AMP page to the non-AMP page and vice versa, in the form of tags in the .

Add the following to the non-AMP page:

<link rel="amphtml" href="https://www.example.com/url/to/amp/document.html">

And this to the AMP page:

<link rel="canonical" href="https://www.example.com/url/to/full/document.html">

are you using AMP pages?

https://support.google.com/webmasters/answer/139066?hl=en

https://www.ampproject.org/docs/fundamentals/discovery

I hope that helps you if not please let me know.

Respectfully,

Tom

JH_OffLimits

Just to confirm, are we suppose to have a canonical on desktop and mobile or just desktop?

This would mean removing the alternate?

Want to confirm everything before iterating this across to others.

We are not using AMP, just a standard site setup.

BlueprintMarketing

What URLs are you using with the “alternate” tag on?

You said
”1. We have multiple brand sites, that have a similar setup. They all have mobile and desktop versions of the sites running on the same URL, both of which show the same content.

2. The server determines whether if you're on a desktop or mobile devices using the header information, and points the user to the site relevant files for the given device.”

thats Dynamic serving same URL

Dynamic serving is a setup where the server responds with different HTML (and CSS) on the same URL depending on which user agent requests the page (mobile, tablet, or desktop).

that would NOT give you the mobile or m.example.com & www.example.com different URLs

**But If you do have a different m.example.com & www.example.com URLs you should use this code or XML site maps **

for different URLs use this:

Annotations in the HTML

On the desktop page (http://www.example.com/page-1), add the following annotation:

<linkrel="alternate"media="only screen="" and="" (max-width:="" 640px)"<="" span="">href="http://m.example.com/page-1"></linkrel="alternate"media="only>

On the mobile page (http://m.example.com/page-1), the required annotation should be:

<linkrel="canonical"href="http: www.example.com="" page-1"=""></linkrel="canonical"href="http:>

This rel="canonical" tag on the mobile URL pointing to the desktop page is required.

Or

Annotations in sitemaps

We support including the rel="alternate"annotation for the desktop pages in sitemaps like this:

<urlsetxmlns="http: www.sitemaps.org="" schemas="" sitemap="" 0.9"<="" span="">xmlns:xhtml="http://www.w3.org/1999/xhtml">

<loc>http://www.example.com/page-1/</loc>
<xhtml:linkrel="alternate"media="only screen="" and="" (max-width:="" 640px)"<="" span="">href="http://m.example.com/page-1"/></xhtml:linkrel="alternate"media="only></urlsetxmlns="http:>

You should have the same URL on mobile and desktop

You should have the same rel canonical tag on your URLs unless and this is a big unless you're talking about using Google AMP?

If the URL you want to be indexed is the same URL point everything to that URL if that makes it easier to understand.

respectfully,

Tom

BlueprintMarketing

The single self-referencing URL will work.

JH_OffLimits

So both mobile and desktop require a self referencing canonical(in both headers)?

Sorry for the questions, just need to make sure! It's a very touchy subject!

BlueprintMarketing

Hey man I understand is a big deal

could you do me a huge favor and run your site through screaming frog SEO spider send me a couple of pages with the domains whited out so I can tell you 100% what to do in this situation because I am basing this on what you have told me and honestly I would like to look at what a tool can show me and that will tell me what I need to do.

Or you can tell me if the mobile version of the site hit's Google's index yes or no?

respectfully,

Tom

JH_OffLimits

I've been told to pass on a URL, thanks for your help Thomas!

https://www.stag.com/

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